Friday in physics was a relief to all of us, even Coats-Haan. Why? Coats-Haan is officially drug free! When we saw her last, it had been a full 24 hours since she'd taken dayquil and nyquil. Did she make it through the weekend? I wonder...I sure hope!
First, we checked homework, but didn't turn anything in. The homework we went over was page 1001 (Goodness! No wonder those physics books are so darn heavy!), numbers 17-19, 21, 29-35, 40-42. Then, we got to watch an exciting video on Chernobyl, which was filmed 10 years after the nuclear explosion that took place there. Before and during the movie, we filled out a true and false worksheet, page 223 in the lab manual.
Coats-Haan also informed us that we will be having a quiz on Monday over the information we have learned about in the past few days, including notes, the example sheet, and homework assignments.
Now, to answer the question of the day. There were several key mistakes at Chernobyl. The biggest mistake I see is that when they were running tests, they shut off all emergency back ups so that nothing would interfere with their testing. Even when the reactor was unstable, they continued to test. Also, the design of the reactor itself was not as well designed as others. What also really bothers me is that there was a huge time delay in informing the nearby cities and towns that the reactor exploded and was releasing dangerous radiation into the atmosphere. Those people should have at least been given a heads up to get out of there as soon as possible.
I hope you all had a happy Star Wars day! May the fourth be with you!
Sunday, May 6, 2012
Friday, May 4, 2012
Thursday, May 3, 2012
05/03 Tuazon
Turned in: Nuclear Fission and Fusion Guiding Reading; Nuclear Fission and Fusion balancing worksheet
Activities: Nuclear Math Notes
Homework: P. 1001, #17-19, 29, 29-35, 40-42
Dear Coats-Haan,
I hope you can read this blog today. That NyQuil and DayQuil really takes its toll. Just in case you were in too much of a stupor to recall anything, I'll give you a recap of what happened today.
You may recall having arrived to school in pajama pants and a Georgia Tech shirt (sort of dressed like Kreider when he forgot to change his clothes yesterday morning). You may also recall saying that Emily was trying to negate her tall marks and telling Kelly to cover Emily mouth before she could do so. You may recall all the seniors leaving us (the cool kids) for a class assembly about graduation.
If you can't recall any of that, you may want to lay off the drugs for a while, ma'am.
Anyway, soon after the seniors abandoned us, you suffered through the slow computer-loading to open up the Nuclear Math Power Point, which has much fewer slides than yesterday's on Nuclear Fusion and Fission. You taught us how to find the number of alpha and beta decays in transmutations, as well as how to find the number of parent nuclei after a certain time. To do the latter, you said to use N=N0e^-λt, where N = number of radioactive nuclei at time t, N0 = original amount, t = time, e = 2.7, and λ = decay constant (measure of isotope stability).
Of course, while you were trying to show us this equation, you were struggling to erase things on the Smart Board (in your words, "It's not the drugs! It's the computer!"). However, despite the delay in my note-taking, I still understand that activity, written as "a" and represents the rate of decay, is equal to ΔN/Δt, or Nλ and can be measured in Becquerels (Bq), which is 1 decay/s, and Curies (Ci), which is 3.7x10^10 decays/s.
In between telling us that ln2=λT(subscript 1/2) (T(subscript 1/2) represents half life), your hatred for a certain brown-haired substitute who stole you keys brewed, and vehemently you ordered Amy to seek her out and retrieve your keys. Your NyQuil called her a bad name.
Love,
Jasmine
Question of the day: How is half life related to the decay constant? Do more radioactive elements have bigger or smaller decay constants?
Answer: Half life is ln2/λ, λ being the decay constant. However, I am not sure about the second part of the QotD. Please have the DayQuil explain to me of the correct answer.
Activities: Nuclear Math Notes
Homework: P. 1001, #17-19, 29, 29-35, 40-42
Dear Coats-Haan,
I hope you can read this blog today. That NyQuil and DayQuil really takes its toll. Just in case you were in too much of a stupor to recall anything, I'll give you a recap of what happened today.
You may recall having arrived to school in pajama pants and a Georgia Tech shirt (sort of dressed like Kreider when he forgot to change his clothes yesterday morning). You may also recall saying that Emily was trying to negate her tall marks and telling Kelly to cover Emily mouth before she could do so. You may recall all the seniors leaving us (the cool kids) for a class assembly about graduation.
If you can't recall any of that, you may want to lay off the drugs for a while, ma'am.
Anyway, soon after the seniors abandoned us, you suffered through the slow computer-loading to open up the Nuclear Math Power Point, which has much fewer slides than yesterday's on Nuclear Fusion and Fission. You taught us how to find the number of alpha and beta decays in transmutations, as well as how to find the number of parent nuclei after a certain time. To do the latter, you said to use N=N0e^-λt, where N = number of radioactive nuclei at time t, N0 = original amount, t = time, e = 2.7, and λ = decay constant (measure of isotope stability).
Of course, while you were trying to show us this equation, you were struggling to erase things on the Smart Board (in your words, "It's not the drugs! It's the computer!"). However, despite the delay in my note-taking, I still understand that activity, written as "a" and represents the rate of decay, is equal to ΔN/Δt, or Nλ and can be measured in Becquerels (Bq), which is 1 decay/s, and Curies (Ci), which is 3.7x10^10 decays/s.
In between telling us that ln2=λT(subscript 1/2) (T(subscript 1/2) represents half life), your hatred for a certain brown-haired substitute who stole you keys brewed, and vehemently you ordered Amy to seek her out and retrieve your keys. Your NyQuil called her a bad name.
Love,
Jasmine
Question of the day: How is half life related to the decay constant? Do more radioactive elements have bigger or smaller decay constants?
Answer: Half life is ln2/λ, λ being the decay constant. However, I am not sure about the second part of the QotD. Please have the DayQuil explain to me of the correct answer.
5/3 qod
How is half life related to the decay constant? Do more radioactive elements have bigger or smaller decay constants?
--ch
--ch
Wednesday, May 2, 2012
Tuesday, May 1, 2012
4/30 Shah
Turned In
We turned in the questions from the atomic nucleus reading.
We turned in the questions from the atomic nucleus reading.
Assignments
We worked on pages 217-220 in our lab manual (which is homework if not completed). We also have a worksheet on carbon dating to finish for homework.
We worked on pages 217-220 in our lab manual (which is homework if not completed). We also have a worksheet on carbon dating to finish for homework.
Class Activities
Well the class started off with tornado drill. As we waited inside the AP room, Coats-Haan told us about the negative side effects of tanning. After that we went over the Cloud Chamber pre-lab questions. We set up the cloud chambers and then Coats-Haan showed us presentation on radiation and its side effects. After that we observed our cloud chamber and saw the particles flying around in the chamber. It was pretty neat. Then we watched a Sense of Scale web stimulation. After that we started the worksheets in our lab manual which are homework if not completed.
Well the class started off with tornado drill. As we waited inside the AP room, Coats-Haan told us about the negative side effects of tanning. After that we went over the Cloud Chamber pre-lab questions. We set up the cloud chambers and then Coats-Haan showed us presentation on radiation and its side effects. After that we observed our cloud chamber and saw the particles flying around in the chamber. It was pretty neat. Then we watched a Sense of Scale web stimulation. After that we started the worksheets in our lab manual which are homework if not completed.
QODI think carbon dating does not give an exact date, but a range of years over which the object may have formed.
Monday, April 30, 2012
Sunday, April 29, 2012
4/29 Scheitlin
In physics class on Friday we had a sub and there were no papers to turn in. We were handed out two papers and they are both due on Monday if they were not finished in class. The first one was the background to the lab we will be doing on Monday, there were a few questions on the back that needed to be finished after you read the lab. The other paper was a reading guide with the packet the sub also handed out. During class we just worked on those two assignments. Overall it was a pretty relaxing class where people worked with who they wanted which to me looked like people just went back with old lab partners that they missed working with just like I worked with Carlie again.
qod- The difference between alpha and beta tracks is that the alpha ones will have thicker tracks than the beta ones.
qod- The difference between alpha and beta tracks is that the alpha ones will have thicker tracks than the beta ones.
Saturday, April 28, 2012
4/27 qod
How will we know the difference in alpha particle tracks and beta particle tracks when we look in the cloud chamber?
-- ch
-- ch
Thursday, April 26, 2012
Wednesday, April 25, 2012
Tuesday, April 24, 2012
Monday, April 23, 2012
04/23 Miley
This Monday started out as any other day in physics would,
by turning in numerous amounts of homework, this including the Bling Project
and Light Wave questions. After turning these in, Mr. Ebersole broke up our
class into groups based on who was at school on Friday. He then explained that
we needed to finish our labs from Friday and begin the camera dissection lab.
Mr. Ebersole repeatedly reminded us all to make sure that the batteries were
out of the camera in order to ensure our safety. After our instructions each group worked on
completing the labs assigned for the remainder of class. At the end of class
Mr. Ebsersole told us that our only “homework” was to work on the test review
and that tomorrow is our time to finish the labs and review for the test on
Wednesday. This concluded our class. Even though this Monday was pretty
ordinary one special thing happened in second period, we had a special guest.
This guest happened to be one of Mr. Ebersole’s professors who were evaluating
his performance so he could learn what he’s doing well as a teacher and where
there is room for improvement. Though none of us really talked to this special
guest, I noticed him admiring my Miami
hoodie.
QOD: How can you measure the focal length of your disposable
camera?
Though I am not certain, I believe that this is the answer.
You would remove the lens, focus it on an image, and move it back & forth
until the image becomes clear. Once the image is clear you can take a ruler to
measure the distance.
Friday, April 20, 2012
4/20 qod
You are attacked by a gang of pirates. They hold you at knife point and tell you that you will have to walk the plank, if you cannot solve a major problem for them. They have a double convex lens and they need to know what the focal length is. What do you do?
--ch
--ch
Thursday, April 19, 2012
Wednesday, April 18, 2012
Tuesday, April 17, 2012
Harrison 4/17
The first thing we did today was turn in the homework from last night (the refraction lab and the reflection and refraction questions). Then, we went over the textbook problems, p. 846 #1-11, 13-15,18.
We then began our presentations. My group went first, explaining why the sky is blue. Jasmine and Matthew were in the play and were unable to make it, but they made a fantastic video that we showed. Next, Charlie, Pat-the-Rat, Kyle, and Alexis presented why the ocean is blue. At the beginning of the next presentation, Kelly loudly shushed everyone, and was congratulated on a job well done by Coats-Haan. Then she, along with Austin, Emily, and Sachi, explained the reasons behind the green flashes at sunrise and sunset. Carlie, Chris, Onur, and Sonny gave a presentation on mirages.
The homework for tonight is a worksheet with Snell's Law problems.
QotD: My favorite presentation was the one about mirages. I had noticed them before while driving but had never realized that they occurred because the hot air next to the ground bends the light up. I also got a kick out of Onur's mannerisms up in front of the class, acting as if he was some kind of philosophy professor or something.
We then began our presentations. My group went first, explaining why the sky is blue. Jasmine and Matthew were in the play and were unable to make it, but they made a fantastic video that we showed. Next, Charlie, Pat-the-Rat, Kyle, and Alexis presented why the ocean is blue. At the beginning of the next presentation, Kelly loudly shushed everyone, and was congratulated on a job well done by Coats-Haan. Then she, along with Austin, Emily, and Sachi, explained the reasons behind the green flashes at sunrise and sunset. Carlie, Chris, Onur, and Sonny gave a presentation on mirages.
The homework for tonight is a worksheet with Snell's Law problems.
QotD: My favorite presentation was the one about mirages. I had noticed them before while driving but had never realized that they occurred because the hot air next to the ground bends the light up. I also got a kick out of Onur's mannerisms up in front of the class, acting as if he was some kind of philosophy professor or something.
Monday, April 16, 2012
4/16 qod
Does light bend toward the normal or away from the normal when it enters a medium that is travels slower in than the initial medium? Explain your answer.
--ch
--ch
Friday, April 13, 2012
Thursday, April 12, 2012
Wednesday, April 11, 2012
4/11 Chao
Today in class, we were given a choice. We could either work on p. 179 – 186 on the remote sensing lab or if we finished the lab last night, we could work on our color presentation projects together. After turning in our color labs on p. 187 – 189, we set off to work. Some groups worked on the lab while other groups hopped on computers and decided to start looking up anything and everything about their designated topic.
Even though the day wasn’t as action-packed as the last two days, our group still managed to get some research into our designated topic: green flashes. Groups of people started congregating towards some computers to be with their teams. Our group stayed on four separate computers and emailed links to ourselves. Apparently green flashes are rare. With the weather and the clouds like it is in Ohio, we’ll probably rarely see one.
Anything of the remote sensing lab that we didn’t complete is homework. The color presentation is due next Tuesday. Rubrics are found on p. 191 of the lab manuel.
QOD: Why do telescopes that detect infrared radiation have to be located outside of the Earth’s atmosphere?
I’m not exactly sure about how to answer this but I’ll try. Because the Earth’s atmosphere is a thick blanket that shields us from ultraviolet waves and produces the greenhouse effect, much of the infrared radiation is absorbed by our atmosphere. Placing a telescope on high mountains would not serve our purpose in gauging infrared radiation because it is only able to measure a small part of the atmosphere. Putting telescopes in outer space can help us gauge the infrared radiation that the atmosphere absorbed on a much grander scale.
Even though the day wasn’t as action-packed as the last two days, our group still managed to get some research into our designated topic: green flashes. Groups of people started congregating towards some computers to be with their teams. Our group stayed on four separate computers and emailed links to ourselves. Apparently green flashes are rare. With the weather and the clouds like it is in Ohio, we’ll probably rarely see one.
Anything of the remote sensing lab that we didn’t complete is homework. The color presentation is due next Tuesday. Rubrics are found on p. 191 of the lab manuel.
QOD: Why do telescopes that detect infrared radiation have to be located outside of the Earth’s atmosphere?
I’m not exactly sure about how to answer this but I’ll try. Because the Earth’s atmosphere is a thick blanket that shields us from ultraviolet waves and produces the greenhouse effect, much of the infrared radiation is absorbed by our atmosphere. Placing a telescope on high mountains would not serve our purpose in gauging infrared radiation because it is only able to measure a small part of the atmosphere. Putting telescopes in outer space can help us gauge the infrared radiation that the atmosphere absorbed on a much grander scale.
4/11 qod
Why do telescopes that detect infrared radiation have to be located outside of the Earth's atmosphere?
--ch
--ch
4/10 Back
Today in Physics we began class by turning in three worksheets: "Starlight, Starbright," the EM table and the Properties of Light guided reading. Afterwards, Mr. Ebersole did a color demonstration using red, blue and green neon tubes attached at an axis. When he spun the wheel, all of the colors mixed to form white. When he then taped off varying sections of each tube, different color combinations could be observed. Trevor made an interesting observation at our table. He said that the reason we hadn't seen purple very well was because Mr. Ebersole had taped the green tube too far down so that when the tubes spun, the centrifugal force of the liquid in the tubes consolidated at the outer side of the tube where the tape did not reach.
Following this demonstration, a presentation was introduced about light and color that is to be given on Tuesday, April 17, 2012. We were given the rubric and requirements necessary to prepare the presentation. Next we worked as a table on a lab about color. We began by putting different colored sheets of glass in front of a flashlight. Then, we switched off between answering questions from the packet we received in class and provided web links on the computer. Anything we did not complete was homework. Also, if we wished to get ahead and be able to work on our presentation the next day, pages 179-185 were to be completed in the lab manual.
QOTD: Why are there different primary colors for light than there are for pigments?
When combining light, red, blue and green are the primary colors. When combining pigments, the primary colors are magenta, yellow and cyan. This is because when combining pigments, light is absorbed and the result is always darker. When combining light, mixing red, blue and green will result in white, as we found in the color demonstration. However, mixing red, blue and green pigments will yield a dark brown.
Following this demonstration, a presentation was introduced about light and color that is to be given on Tuesday, April 17, 2012. We were given the rubric and requirements necessary to prepare the presentation. Next we worked as a table on a lab about color. We began by putting different colored sheets of glass in front of a flashlight. Then, we switched off between answering questions from the packet we received in class and provided web links on the computer. Anything we did not complete was homework. Also, if we wished to get ahead and be able to work on our presentation the next day, pages 179-185 were to be completed in the lab manual.
QOTD: Why are there different primary colors for light than there are for pigments?
When combining light, red, blue and green are the primary colors. When combining pigments, the primary colors are magenta, yellow and cyan. This is because when combining pigments, light is absorbed and the result is always darker. When combining light, mixing red, blue and green will result in white, as we found in the color demonstration. However, mixing red, blue and green pigments will yield a dark brown.
Tuesday, April 10, 2012
Monday, April 9, 2012
4/9 Armour
Today in physics, we received new teams, so we made our teammate farewells and got new blue sheets. Next, Coats-Haan heated up marshmallows in a microwave without the plate spinning, so we could determine the wave length. Then we found the speed of light using the given frequency and the wave length I measured. Since I measured the wave length, we all know our answer was very close to the accepted value. We could find the speed of light by using the equation v= wave length * frequency. After the in-class demonstration, Coats-Haan set us loose to work on Star Light, Star Bright (pp. 175-176), The Electromagnetic Spectrum (pp. 177-178), or Properties of Light reading (our homework).
Wednesday, March 28, 2012
Friday, March 23, 2012
Thursday, March 22, 2012
2/22 Shah
Turned in
Class activities
Today we continued the sound lab marathon from yesterday. Everyone scrambled in attempt to finish the lab today; however, most (if not all) of us did not finish it and so we will have the beginning of class tomorrow to begin it. Interestingly enough, while working on the part with the mic, my group forgot that we had a recorder at our convenience to create the sounds. We took the fun route. Or at least Ethan did. Ethan sang/talked/made noise into the mic instead. Yes, we’re just creative. J Not really, we’re just forgetful.
QOD
Ironic enough, the sound barrier section is the section my group still has to complete. So I’m not 100% sure, but I think traveling through carbon dioxide would slow the speed of sound.
Assignments
Tonight we have no homework in Honors Physics. J However, given that we have a sound test next Monday and the exam next Friday, it would be advisable to start the review packets. Class activities
Today we continued the sound lab marathon from yesterday. Everyone scrambled in attempt to finish the lab today; however, most (if not all) of us did not finish it and so we will have the beginning of class tomorrow to begin it. Interestingly enough, while working on the part with the mic, my group forgot that we had a recorder at our convenience to create the sounds. We took the fun route. Or at least Ethan did. Ethan sang/talked/made noise into the mic instead. Yes, we’re just creative. J Not really, we’re just forgetful.
QOD
Ironic enough, the sound barrier section is the section my group still has to complete. So I’m not 100% sure, but I think traveling through carbon dioxide would slow the speed of sound.
Wednesday, March 21, 2012
Tuesday, March 20, 2012
03/20 Wheeler
Today, March 20th, is a rather exciting blog day for me. Why? Well, first off, I always find something cool or exciting about the blog. Second, this is only my second blog on a non-test day! So, I get to explain the fantastic physics we learned today, not just describe how we scribbled with pencils and punched numbers into the calculator the entire period, all the while stressing if number seventeen is correct. For Coats-Haan's sake, I hope our test-taking doesn't look as boring as the sophomores during OGT week.
We turned in the Shockwaves Worksheet (if you did not finish it yesterday) and we checked page 507, numbers 70-76 in our physics book (which could stand to lose some weight, I might add). Coats-Haan piped in at this time to remind Chris Roseblossom he needs to get off the streak of not doing homework, reminding him that he was one of the smartest, laziest kids she knows. I agree with that statement. Also, keep in mind that our exams are next week! So, working on the 3rd quarter exam review is not a bad idea.
I rather liked today's notes. There were only twelve slides, I believe, either way not enough to make my hand hurt. We learned the difference between intensity and loudness. Intensity is the rate at which the sound energy flows through a unit area normal to the direction of propagation. Loudness (or volume, as the slides pointed out) depends on an auditory sensation in the consciousness of a human listener and isn't quantifiable.
Okay, so here are a few more handy equations we learned in class today. Try to make some room in your brain for a couple more, okay? We are three fourths of the way through the year. We can do this!
Intensity = Power/Area
Or, the shorter version (aka Chris Roseblossom's version), I = P/A
P is in watts, A is in square meters, and I is in watts per square meter.
The normal area is the surface area of a sphere, 4 times pi times radius squared (hello, old friend geometry!).
B = 10 log (I/Io)
Io = 10-12 watts per meter squared
B is the relative intensity in decibels
Recalling those log properties we learned (again) a few months ago in honors pre-calc might also do you some good.
For homework, we have to complete the pair check (if not finished in class) and do two worksheets, one titled "Loudness and Intensity Homework" (I would have never guessed) and the other "Detecting Decibels/I've Got Your Frequency."
And finally, to answer the question of the day. Because of the large range of intensities over which the ear is sensitive, we use the logarithmic scale.
We turned in the Shockwaves Worksheet (if you did not finish it yesterday) and we checked page 507, numbers 70-76 in our physics book (which could stand to lose some weight, I might add). Coats-Haan piped in at this time to remind Chris Roseblossom he needs to get off the streak of not doing homework, reminding him that he was one of the smartest, laziest kids she knows. I agree with that statement. Also, keep in mind that our exams are next week! So, working on the 3rd quarter exam review is not a bad idea.
I rather liked today's notes. There were only twelve slides, I believe, either way not enough to make my hand hurt. We learned the difference between intensity and loudness. Intensity is the rate at which the sound energy flows through a unit area normal to the direction of propagation. Loudness (or volume, as the slides pointed out) depends on an auditory sensation in the consciousness of a human listener and isn't quantifiable.
Okay, so here are a few more handy equations we learned in class today. Try to make some room in your brain for a couple more, okay? We are three fourths of the way through the year. We can do this!
Intensity = Power/Area
Or, the shorter version (aka Chris Roseblossom's version), I = P/A
P is in watts, A is in square meters, and I is in watts per square meter.
The normal area is the surface area of a sphere, 4 times pi times radius squared (hello, old friend geometry!).
B = 10 log (I/Io)
Io = 10-12 watts per meter squared
B is the relative intensity in decibels
Recalling those log properties we learned (again) a few months ago in honors pre-calc might also do you some good.
For homework, we have to complete the pair check (if not finished in class) and do two worksheets, one titled "Loudness and Intensity Homework" (I would have never guessed) and the other "Detecting Decibels/I've Got Your Frequency."
And finally, to answer the question of the day. Because of the large range of intensities over which the ear is sensitive, we use the logarithmic scale.
Monday, March 19, 2012
03/19 Tuazon
Turned in:
Doppler Effect Simulation
16.9 and 16.10 Guided Reading
Returned:
Sound Reading Questions
Class activities:
Doppler Effect Notes
Shockwaves Worksheet
Homework:
Shockwaves Worksheet (if not finished in class)
Honors Physics 3rd Quarter Test Review (begin working on this)
P. 507, #70-76 in our textbook
Study for sound test on Monday
-------
With my Doppler Effect Simulation and Guided Reading already turned in before school started (I had to come in early because my computer would not run the simulation) and my Sound Reading Questions already picked up out of my folder, I went up to the board to write down the honors physics homework really quick. To my side, I could hear Jeff and a few other people complaining about something Mr. Ebersole said, and as I tuned in, I heard great news that we had a sound test on Monday.
Yeah––the first real test we would have in weeks would be on exam week.
I joined in with the petty whining for a while, with Mr. Ebersole telling us to calm down, before returning back to my seat and watching as Mr. Ebersole prepared to show us some equipment to demonstrate the Doppler Effect.
One thing I remember them comparing the two pieces of equipment they used. One was a really expensive metal rod with a tone box attached to the end of it that could probably decapitate Mr. Ebersole if he did not move out of the way, while the other one was a rubber tube that Ms. Grote bought for $1 at a toy store that did not even need the tone box at the end to demonstrate the same thing. Coats-Haan said something about how East is obviously superior because of this.
Anyway, for the demonstration, Mr. Ebersole waved both sounding objects around his head, and the pitch became higher as the source moved closer to us, and the pitch lowered moving away from us. This is because of the source's velocity.
Then we went off to take notes, which Mr. Ebersole was really excited about ("Oh my gosh, we get to skip a ton of slides today! We've just made this powerpoint go from 19 slides to 6 slides!").
We learned that the general form for the Doppler Effect is:
fo = fs (1 ± vo/v) / (1 ∓ vs/v)
The variables for this are:
fo = frequency observed
fs = frequency of source
vo = velocity of observer
vs = velocity of source
v = speed of sound
Note: The upper signs of the + or - sections of the equations are used when the observer or source is going toward the other, and the bottom signs of the + or - sections of the equations are used when the observer or source is going away from the other.
We also did example problem #6 and #7, in which all you have to do is plug in the known values to find the frequency of the source and the frequency observed, respectively. The answer for #6 is 490 Hz, and the answer for #7 is 410 Hz.
Additional note from questions other students asked in class:
- Depending on direction the observer and source are going in relation to each other, you may use both top signs, both bottom signs, or one of each sign in the equation.
- If either the observer or source is stationary, their respective top or bottom portion of the equation will end up being zero.
- As long as the speed of the observer and source stay the same, the frequency observed will be the same, even if one catches up with the other. However, at the point when the observer is on the opposite side of the source, the frequency observed will be different (yet still consistent on that side of the source).
Finally, we wrapped our our period working on a Shockwaves Worksheet.
This is what my table concluded (We also got 100% on our worksheet according to HAC, so this information should be accurate)
- As speed increases, the angle of the spacecraft to the shockwave gets narrower
- The distance of the the spacecraft goes divided by the distance the shockwave goes (its radius) is the relative speed of the spacecraft to the speed of sound.
For example: If the spacecraft moves 8 cm, and the shockwave has a radius of 2 cm, 8 cm divided by 2 cm is 4, meaning the spacecraft is going 4 times the speed of sound.
Wow, that was a lot of information. Feel free to ask for clarification.
-------
Question of the Day:
Describe a situation where both the signs are positive in the Doppler Effect Equation.
--ch
Answer: A situation in which the observer is going toward the source and the source is going away from the observer would result in both signs being positive in the Doppler Effect Equation. Such a situation may be Trevor moving toward Chris, trying to get him to work on stuff for our Rube Goldberg Machine, while Chris is covering his ears, making a really annoying sound to block out Trevor's requests, and running away.
Doppler Effect Simulation
16.9 and 16.10 Guided Reading
Returned:
Sound Reading Questions
Class activities:
Doppler Effect Notes
Shockwaves Worksheet
Homework:
Shockwaves Worksheet (if not finished in class)
Honors Physics 3rd Quarter Test Review (begin working on this)
P. 507, #70-76 in our textbook
Study for sound test on Monday
-------
With my Doppler Effect Simulation and Guided Reading already turned in before school started (I had to come in early because my computer would not run the simulation) and my Sound Reading Questions already picked up out of my folder, I went up to the board to write down the honors physics homework really quick. To my side, I could hear Jeff and a few other people complaining about something Mr. Ebersole said, and as I tuned in, I heard great news that we had a sound test on Monday.
Yeah––the first real test we would have in weeks would be on exam week.
I joined in with the petty whining for a while, with Mr. Ebersole telling us to calm down, before returning back to my seat and watching as Mr. Ebersole prepared to show us some equipment to demonstrate the Doppler Effect.
One thing I remember them comparing the two pieces of equipment they used. One was a really expensive metal rod with a tone box attached to the end of it that could probably decapitate Mr. Ebersole if he did not move out of the way, while the other one was a rubber tube that Ms. Grote bought for $1 at a toy store that did not even need the tone box at the end to demonstrate the same thing. Coats-Haan said something about how East is obviously superior because of this.
Anyway, for the demonstration, Mr. Ebersole waved both sounding objects around his head, and the pitch became higher as the source moved closer to us, and the pitch lowered moving away from us. This is because of the source's velocity.
Then we went off to take notes, which Mr. Ebersole was really excited about ("Oh my gosh, we get to skip a ton of slides today! We've just made this powerpoint go from 19 slides to 6 slides!").
We learned that the general form for the Doppler Effect is:
fo = fs (1 ± vo/v) / (1 ∓ vs/v)
The variables for this are:
fo = frequency observed
fs = frequency of source
vo = velocity of observer
vs = velocity of source
v = speed of sound
Note: The upper signs of the + or - sections of the equations are used when the observer or source is going toward the other, and the bottom signs of the + or - sections of the equations are used when the observer or source is going away from the other.
We also did example problem #6 and #7, in which all you have to do is plug in the known values to find the frequency of the source and the frequency observed, respectively. The answer for #6 is 490 Hz, and the answer for #7 is 410 Hz.
Additional note from questions other students asked in class:
- Depending on direction the observer and source are going in relation to each other, you may use both top signs, both bottom signs, or one of each sign in the equation.
- If either the observer or source is stationary, their respective top or bottom portion of the equation will end up being zero.
- As long as the speed of the observer and source stay the same, the frequency observed will be the same, even if one catches up with the other. However, at the point when the observer is on the opposite side of the source, the frequency observed will be different (yet still consistent on that side of the source).
Finally, we wrapped our our period working on a Shockwaves Worksheet.
This is what my table concluded (We also got 100% on our worksheet according to HAC, so this information should be accurate)
- As speed increases, the angle of the spacecraft to the shockwave gets narrower
- The distance of the the spacecraft goes divided by the distance the shockwave goes (its radius) is the relative speed of the spacecraft to the speed of sound.
For example: If the spacecraft moves 8 cm, and the shockwave has a radius of 2 cm, 8 cm divided by 2 cm is 4, meaning the spacecraft is going 4 times the speed of sound.
Wow, that was a lot of information. Feel free to ask for clarification.
-------
Question of the Day:
Describe a situation where both the signs are positive in the Doppler Effect Equation.
--ch
Answer: A situation in which the observer is going toward the source and the source is going away from the observer would result in both signs being positive in the Doppler Effect Equation. Such a situation may be Trevor moving toward Chris, trying to get him to work on stuff for our Rube Goldberg Machine, while Chris is covering his ears, making a really annoying sound to block out Trevor's requests, and running away.
3/19 qod
Describe a situation where both the signs are positive in the Doppler effect equation.
--ch
--ch
Friday, March 16, 2012
Tuesday, March 13, 2012
Friday, March 9, 2012
3/9 qod
What do you think were some of the biggest barriers to making the windmills lift more weight?
--ch
--ch
Thursday, March 8, 2012
Wednesday, March 7, 2012
Miley 3/7
To begin the class period, Mr. Ebersole reminded us of all the upcoming things and assignments due: Section 4 Lab and Homework are due tomorrow (3/8), Windmills on Friday (3/9), and our third electricity quiz tomorrow. We then continued by learning about Ohm’s Law and Equivalent resistance. Ohm’s law is V=iR and helps prove that resistance and current are inversely proportional. Equivalent resistance is when the resistance of the single resistor would produce the same effect as what is produced by the network. Both of these concepts are the math used to prove what we have been learning in the circuit labs. After taking our notes and finishing the example problems, Mr. Ebersole handed out a circuit worksheet that review what we have previous learned and the new concepts learned today. This worksheet is also due tomorrow (3/8). DON’T FORGET: 3 DAYS TILL WINDMILLS!
QOD: Use the mathematical equations for finding equivalent resistance to explain the results you observed for bulb brightness in the lab.
As seen in the equations for resistance equivalence, series and parallel circuits vary in how they are calculated. For a series, you just add the resistances together. And for a parallel circuit, you add the reciprocals for each resistor. As we’ve seen in the labs, the parallel circuits provide more pathways for the current to travel through, which can help decrease the resistance. In a series, one pathway is used which can sometimes cause more resistance. When executing the equations with actual problems, we can see that these ideas hold true. With less resistance the bulb can be brighter, as we’ve seen in parallel circuits and with more resistance the bulb may be dimmer, as seen in series. Though I’m confident with this answer, I’m not 100% sure that I’m correct.
3/8 qod
Use the mathematical equations for finding equivalent resistance to explain the results you observed for bulb brightness in the lab.
--ch
--ch
Tuesday, March 6, 2012
Monday, March 5, 2012
leonow 3/5
We continued working on our circuit lab. Section 3 was to be completed by the end of the period today and the homework was assigned for tomorrow. If you don't finish section 3, you may use some time at the beginning of the period tomorrow. The lab, including section 4, is to be done no later than Wednesday. Don't forget, the windmill/Rube Goldberg machine is due Friday and they can be brought in before school any day this week.
The answer to the question of the day is when more bulbs are added in parallel, the total resistance increases and current is allowed to flow more freely, indicated by the increased brightness of the bulbs. On the other hand, when more bulbs are added in series, the total resistance decreases and the current moves slower.
The answer to the question of the day is when more bulbs are added in parallel, the total resistance increases and current is allowed to flow more freely, indicated by the increased brightness of the bulbs. On the other hand, when more bulbs are added in series, the total resistance decreases and the current moves slower.
3/5 qod
If you add bulbs in parallel, what happens to resistance and flow through the battery?
If you add bulbs in series, what happens to resistance and flow through the battery?
--ch
If you add bulbs in series, what happens to resistance and flow through the battery?
--ch
Friday, March 2, 2012
3/2 qod
You have a circuit with multiple switches and bulbs. You are asked to rank the bulbs in all possible switch positions. Please describe how you should report your answer.
-ch
-ch
Thursday, March 1, 2012
3/1 qod
There are two circuits. One circuit has two bulbs in series. The other circuit has two bulbs in parallel. Which circuit has the brighter bulbs? Explain why.
--ch
--ch
Wednesday, February 29, 2012
Tuesday, February 28, 2012
2/28 qod
You have a battery connected to a bulb in a complete circuit. What do you know about the flow through the circuit?
--ch
--ch
Monday, February 27, 2012
Saturday, February 25, 2012
2/24 Chao
I must have been in a very comatose state when I went home yesterday because I did my blog a day early. I’m still in a slight comatose state but, you know, things just happen.
Either way, today’s board with its purple message stated that we had keys waiting on our desks for our electrostatic force worksheets. #12 was a pretty difficult problem. That’s one to review in my opinion.
After answering some questions, especially regarding pesky #12, Coats-Haan gave us a teacher talk regarding the science courses we could take next year. Everyone should take Honors Anatomy because in her words, “Everyone needs to know about their own body.” Advice ranged from “I will not recommend anybody for Earth and Space Science” to being politically correct about a certain half of the kids in our grade that took Chemistry last year.
Then came the AP Physics talk. She stated that the class is very difficult and that mechanics, all the stuff we spent from August to February learning, would be covered in just a few short weeks when school started for us next year. Those that plan on taking AP that is. Tiger moms have some influence, I guess.
She emphasized that she did not want us to start the AP review packet until the weekend before school started. And she looked at me. Don’t worry, Coats-Haan. I may not be in a comatose state during those last few weeks of summer, but I certainly don’t have motivation to start review packets in May.
After the teacher talk session, we jumped into our next activity: the 12-page lab from pages 141 to 160. This lab is split up into several sections, each examining a certain aspect of electricity and circuits. We will be working on this lab during the next few weeks. Every exercise / homework problem must be done on a separate piece of paper. It is essential that we label our papers clearly.
We began section 1 by examining all of the different possible ways to light a light bulb with one bulb, one wire, and one battery. Then, we were supposed to start examining a flashlight. We learned that a circuit to light the light bulb is made when the light bulb is wrapped in wire and it is touching one end while the wire is touching the other end.
There is no homework this weekend but there is a quiz on Monday over Coulomb’s Law and other information regarding the worksheet we checked.
Question of the Day: What is your operational definition for a circuit?
My operational definition for a circuit would be first to obtain a battery or other form of stored electrical energy with a positive and negative end. Obtain metal wire since it conducts electricity easily. If the circuit is concerned with powering a certain device, attach the wire to the device. Have the device touch one end of the battery and have the rest of the wire touching the other end of the battery. I think this is the operational definition, although I’m not sure.
Either way, today’s board with its purple message stated that we had keys waiting on our desks for our electrostatic force worksheets. #12 was a pretty difficult problem. That’s one to review in my opinion.
After answering some questions, especially regarding pesky #12, Coats-Haan gave us a teacher talk regarding the science courses we could take next year. Everyone should take Honors Anatomy because in her words, “Everyone needs to know about their own body.” Advice ranged from “I will not recommend anybody for Earth and Space Science” to being politically correct about a certain half of the kids in our grade that took Chemistry last year.
Then came the AP Physics talk. She stated that the class is very difficult and that mechanics, all the stuff we spent from August to February learning, would be covered in just a few short weeks when school started for us next year. Those that plan on taking AP that is. Tiger moms have some influence, I guess.
She emphasized that she did not want us to start the AP review packet until the weekend before school started. And she looked at me. Don’t worry, Coats-Haan. I may not be in a comatose state during those last few weeks of summer, but I certainly don’t have motivation to start review packets in May.
After the teacher talk session, we jumped into our next activity: the 12-page lab from pages 141 to 160. This lab is split up into several sections, each examining a certain aspect of electricity and circuits. We will be working on this lab during the next few weeks. Every exercise / homework problem must be done on a separate piece of paper. It is essential that we label our papers clearly.
We began section 1 by examining all of the different possible ways to light a light bulb with one bulb, one wire, and one battery. Then, we were supposed to start examining a flashlight. We learned that a circuit to light the light bulb is made when the light bulb is wrapped in wire and it is touching one end while the wire is touching the other end.
There is no homework this weekend but there is a quiz on Monday over Coulomb’s Law and other information regarding the worksheet we checked.
Question of the Day: What is your operational definition for a circuit?
My operational definition for a circuit would be first to obtain a battery or other form of stored electrical energy with a positive and negative end. Obtain metal wire since it conducts electricity easily. If the circuit is concerned with powering a certain device, attach the wire to the device. Have the device touch one end of the battery and have the rest of the wire touching the other end of the battery. I think this is the operational definition, although I’m not sure.
Friday, February 24, 2012
Thursday, February 23, 2012
2/23 Armour
*This is awkward because it was actually my day because Jeff and I switched, so I am going to post my version of the blog for february 23rd also.
Today in physics, we learned more about electrostatic subjects. However, first we turned in our homework from the night before (reading guide). Then we took notes about coulomb’s law, superposition principle, and conservation of charge. The notes are below. Mr. Ebersole handed out the practice problems sheet and we completed that together as a class. Then we worked on the pair check, if one finished then you got to work on your homework. It was a very exciting day in physics.
Electrostatic Notes
1. Coulomb’s law
a. Consider two static point charges
b. Each charge experiences a force along a line connection the two charges
c. The magnitude of the force is given by:
i. F=k|q1||q2|/r2
d. Where k = 8.99*10^9 n*m2/c2
e. q1 and q2 are the magnitudes of the two charges
f. r is the distance between the charges
2. Superposition Principle
a. We can add the electric forces as vectors
b. Opposites attract
c. Like charges repel
3. Conductors- readily conduct electric charge from one point to another i.e. metals
4. Insulators- charge placed on one part of the surface remains localized i.e. wood, rubber, and glass
5. Conservation of Charge
a. Although charge moves from place to place, net charge is never created or destroyed
6. Basic Units of Charge
a. Electrons have a mass of 9.1*10^-31kg and charge of -1.6*10^-19
b. Protons have a mass of 1.67*10^-27 and a charge of 1.6*10^-19
Q.O.D.
What does superposition mean?
Superposition means we can add the electric forces as if they are vectors.
Today in physics, we learned more about electrostatic subjects. However, first we turned in our homework from the night before (reading guide). Then we took notes about coulomb’s law, superposition principle, and conservation of charge. The notes are below. Mr. Ebersole handed out the practice problems sheet and we completed that together as a class. Then we worked on the pair check, if one finished then you got to work on your homework. It was a very exciting day in physics.
Electrostatic Notes
1. Coulomb’s law
a. Consider two static point charges
b. Each charge experiences a force along a line connection the two charges
c. The magnitude of the force is given by:
i. F=k|q1||q2|/r2
d. Where k = 8.99*10^9 n*m2/c2
e. q1 and q2 are the magnitudes of the two charges
f. r is the distance between the charges
2. Superposition Principle
a. We can add the electric forces as vectors
b. Opposites attract
c. Like charges repel
3. Conductors- readily conduct electric charge from one point to another i.e. metals
4. Insulators- charge placed on one part of the surface remains localized i.e. wood, rubber, and glass
5. Conservation of Charge
a. Although charge moves from place to place, net charge is never created or destroyed
6. Basic Units of Charge
a. Electrons have a mass of 9.1*10^-31kg and charge of -1.6*10^-19
b. Protons have a mass of 1.67*10^-27 and a charge of 1.6*10^-19
Q.O.D.
What does superposition mean?
Superposition means we can add the electric forces as if they are vectors.
2/23 Chao
Mr. Ebersole’s right. We kind of need to wake up. Or at least I need to.
Almost sleepwalking into physics today, I dropped my pile of books onto my desk and of course, my eyes habitually glanced at the board. We turned in our 18.1-18.5 guided readings and out of the blue folders came our “Electricity Stuff” worksheet and our homemade roller coaster grades / problems.
Then, Mr. Ebersole put up lightning strikes on the SmartBoard and held a balloon (inflated of course) and a piece of rabbit fur. He then rubbed the balloon with the rabbit fur. Nothing elaborately confusing. But the next thing he did certainly had all of us captivated.
He moved the balloon toward an empty pop can. The empty pop can followed the balloon when he moved the balloon further away from it! After several more tries, he successfully had the balloon freely move the pop can, similar to enamored couples freely following each other in the hallway. Kyle thought it was magic. I did too.
He explained that because a metal allows electrons to move freely about it, the pop can can create a positive side and a negative side. He also explained that since the rabbit transferred electrons to the balloon and resulting in a negative charge, the pop can’s electrons fled from the electrons from the balloon and thus, the side closest to the balloon had a positive charge. This positive charge, combined with the fact that opposite charges attract, caused the can to move toward the balloon.
We then popped into notes. Terms like Coulomb’s Law, Superposition Principles, Conductors, Insulators, Conservation of Charge, Basic units of charge came up during class.
Coulomb’s law is essentially saying that the force exerted by 2 static point charges is measured by F = (k * |q1| * |q2|)/r2. K is the constant 8.99 x 109 Nm2/C2. Q1 and q2 are charges measured in Coulombs and r is the distance between them in meters. Similar to the Law of Universal Gravitation.
The superposition principle (Question of the Day “What does superposition mean?”) simply states that electrostatic forces are vector quantities, with a magnitude and direction. Thus, superposition means that we can add these electrostatic forces in a FOXY table since they are vectors.
Conductors can readily conduct electric charge from one point to another while insulators can’t. Charge, like energy, is conserved and only moves from place to place, not created nor destroyed.
Basic units of charge are electrons (mass = 9.1 x 10-31 kg, charge = -1.60x10-19C) and protons (mass = 1.67 x 10-27, charge = 1.60x10-19C).
We then did a pair check. For homework, there is a worksheet with all sorts of electrostatic forces problems.
Wednesday, February 22, 2012
2/22 Back
As we turned in our crazy coasters practice problems from the previous night, very few of us knew what a momentous day we had in store for ourselves. It was the end of a phase in our physics careers; the start of another. Mechanics were finished; electricity had just begun.
We embarked on this new journey by first discovering the reactions produced by a Van de Graaff generator. We learned about the belt that runs inside the generator that creates electricity and charges the sphere. We also learned about physics lab-partner marriages. With all due respect, I think Sonny and I will find our own respective spouses. After seeing electricity run through Miranda, Shachi, Kyle, Jack, Carlie and I, we set out to complete the Electricity Stuff worksheet that Mr. E had passed out to us. We learned a bar trick with rabbit fur, used tape to generate an electric charge, and watched Mr. E smash lifesavers in the dark room. We completed that worksheet with plenty of time left in class and turned it in to the second period folder. Pretty much everyone then got a jump start on their homework, which was a guided reading worksheet on 18.1-18.5. It is due today.
QOTD: Why do wintergreen lifesavers spark when you bite into them?
The lifesavers are made of crystalline sugars that break and release electrons into the atmosphere upon being bitten, or smashed, as the case may be. Then, all of the freed electrons search for a new home in the atmosphere. The newly-positive atoms of the mint, the nitrogen in the air, and the electrons from the mint collide in a way that produces a faint blue light in the right conditions.
We embarked on this new journey by first discovering the reactions produced by a Van de Graaff generator. We learned about the belt that runs inside the generator that creates electricity and charges the sphere. We also learned about physics lab-partner marriages. With all due respect, I think Sonny and I will find our own respective spouses. After seeing electricity run through Miranda, Shachi, Kyle, Jack, Carlie and I, we set out to complete the Electricity Stuff worksheet that Mr. E had passed out to us. We learned a bar trick with rabbit fur, used tape to generate an electric charge, and watched Mr. E smash lifesavers in the dark room. We completed that worksheet with plenty of time left in class and turned it in to the second period folder. Pretty much everyone then got a jump start on their homework, which was a guided reading worksheet on 18.1-18.5. It is due today.
QOTD: Why do wintergreen lifesavers spark when you bite into them?
The lifesavers are made of crystalline sugars that break and release electrons into the atmosphere upon being bitten, or smashed, as the case may be. Then, all of the freed electrons search for a new home in the atmosphere. The newly-positive atoms of the mint, the nitrogen in the air, and the electrons from the mint collide in a way that produces a faint blue light in the right conditions.
Tuesday, February 21, 2012
02/21 Wheeler
Today was no ordinary day in honors physics. Of course, no day in honors physics is ordinary, but this one was particularly special. We tested our roller coasters today! I always get to blog about the exciting things like tests (my favorite!) and spirit days and fun experiments. I know everyone else is quite jealous of this. I am dearly sorry.
At the beginning of class, we put the finishing touches on our coasters (just another piece of duct tape can't hurt, right?) and conversed about our calculations, coming to the conclusion of where the golden hula hoop target should be placed on Main Street. The location of this hula hoop meant life or death for our grades on this project. You can imagine that Matt and I were extremely calm about this...Anyway, there were plenty of unique designs of coasters, and almost all of them landed in the hula hoop on the first try. Except my group. We were special. We were so special that we managed to hit the hula hoop on the third time, which is always a charm, as we all know.
After proving (or failing to prove) the worthiness of our roller coasters, we headed back to the physics room and turned in our calculations for our roller coaster. We then began on a worksheet titled "Roller Coaster Review," which is due tomorrow if you did not finish it in class, like me. Judging by the title, I still have no idea what the worksheet is about. I'm just kidding; the worksheet reviews determining force factors and necessary speeds for a circular loop on, of all things, a roller coaster.
I would like to suggest that we apply our wonderful knowledge of roller coasters by visiting Kings Island when it re-opens in the warmer weather.
On to the question of the day. Woohoo! Although, my confidence in myself for answering this question appropriately is a bit low after today's experiences. We determined the distance the hula hoop needed to be placed from the balcony by using the information we gained from the photogate timer and the small-scale set up of our project. We used the speed of the marble, the height of the balcony from Main Street, the approximate time it would take the marble to reach Main Street, and the small-scale distance the marble landed from the table. Oh, and we also used those good old kinematics equations (they just don't go away, do they?) and the energy equations.
I can't wait until next blog! Maybe I will get a test day...or an awesome experiment day!
At the beginning of class, we put the finishing touches on our coasters (just another piece of duct tape can't hurt, right?) and conversed about our calculations, coming to the conclusion of where the golden hula hoop target should be placed on Main Street. The location of this hula hoop meant life or death for our grades on this project. You can imagine that Matt and I were extremely calm about this...Anyway, there were plenty of unique designs of coasters, and almost all of them landed in the hula hoop on the first try. Except my group. We were special. We were so special that we managed to hit the hula hoop on the third time, which is always a charm, as we all know.
After proving (or failing to prove) the worthiness of our roller coasters, we headed back to the physics room and turned in our calculations for our roller coaster. We then began on a worksheet titled "Roller Coaster Review," which is due tomorrow if you did not finish it in class, like me. Judging by the title, I still have no idea what the worksheet is about. I'm just kidding; the worksheet reviews determining force factors and necessary speeds for a circular loop on, of all things, a roller coaster.
I would like to suggest that we apply our wonderful knowledge of roller coasters by visiting Kings Island when it re-opens in the warmer weather.
On to the question of the day. Woohoo! Although, my confidence in myself for answering this question appropriately is a bit low after today's experiences. We determined the distance the hula hoop needed to be placed from the balcony by using the information we gained from the photogate timer and the small-scale set up of our project. We used the speed of the marble, the height of the balcony from Main Street, the approximate time it would take the marble to reach Main Street, and the small-scale distance the marble landed from the table. Oh, and we also used those good old kinematics equations (they just don't go away, do they?) and the energy equations.
I can't wait until next blog! Maybe I will get a test day...or an awesome experiment day!
Monday, February 20, 2012
2/16 Tuazon
Quick stuff to know:
- Turned in: Nothing
- Returned: Energy test
- Assignments made: Finish Crazy Coasters calculations (Plus working on your group's windmill or Rube Goldberg machine)
Detailed stuff:
I walked into my second class period on this fine February the 16th of the year 2012 thinking about how I was going to prepare for yet another gathering-info-to-write-my-blog-with session. Then I forgot all about it two seconds later.
No matter. My memory will serve me well.
So on that fine, fine day, after my short term memory threw out the thoughts of my blog, we picked up our Energy Test from our folders.
We began the class period with Coats-Haan and Mr. Ebersole asking us what were some good ways and bad ways of measuring the exit velocity of the marble as it left our rollercoasters. Two good ways were to use one of the photogates around the room (which Coats-Haan shows us how to use) and to measure it using the 3rd kinematics equation and the distance that the marble travels from being ejected at table height until it hits the ground. (I detail both of the good methods in my answer to the QotD.) One of the bad ways included using timers because they would be unreliable due to the great amount of human error involved in stopping and starting the them. Using Ui + Ki = Uf + Kf could also be considered a bad way because even though it gives a ballpark exit velocity, it does not take friction into consideration.
Afterwards, Mr. Ebersole dismissed us from our tables so we could continue working on our ever-so-innovative rollercoasters and so we could experimentally measure the exit velocity using the two good methods.
Matt's group had to finish putting their through-the-cardboard rollercoaster together. It was actually beginning to look sort of bulky and intimidating with all the tubing and double cardboard panels everywhere. It was like a Franken-coaster. However, Coats-Haan and Mr. Ebersole did say that many other groups throughout the day were copying their raging through-the-cardboard design. Good for them, setting precedents and whatnot.
Back at our overly duck-taped, one-loop wonder, Trevor, Chris, Aimee and I went straight for the photogate at the end of the room to measure our exit velocity. It took us a while, though. Sometimes, because the beginning of our track was so steep, the marble would not land on the track until a second or two later and the marble would have an usually slow exit velocity from not being able to pick up the full speed from the tubing. Much of our time was spent stacking and removing Chris' folders and trying to get the photogate to sense that the marble was passing through it. Late we realized that the marble was simply shooting out a little too high for the photogate to sense it, and we all mentally smacked ourselves in the faces.
Measuring with the 3rd kinematics equation method was a little more eventful. We propped our rollercoaster board up on top of Mr. Ebersole's table back by the AP lab, and after we measured the height of the table (0.8 m), we had a great time trying to see if the marble would land in the same spot every time (this is not a necessary step to finding the exit velocity). After our initial marble release, Chris put his eraser approximately where the marble landed (about .9 m away in the x-direction from the end of the rollercoaster) and we continued putting the marble through the coaster to see how often the marble would land in the area around the eraser.
To end the period, we relaxed and finished our final calculations on the Crazy Coasters worksheet.
Note: For #13, when you use the 3rd kinematics equation, use a height of 4 m instead of the 4.6 m (a measurement which has been wrong for years, apparently). The time you get as your answer in #13 will be used in the 3rd kinematics equation as well for #14.
Question of the Day:
Q: How do you measure exit velocity with the photogate timer? How do you measure it by projecting it off the table?
A: To measure exit velocity with the photogate timer, you take the diameter of the ball and divide it by the change in time from the moment the ball entered the photogate to the moment it left the photogate.
To measure the exit velocity by projecting the ball off the table, you use the 3rd kinematics equation for the motion in the y-direction to solve for the time it takes to touch the ground. You then take the distance in the x-direction that the ball traveled and divide it by the time you found using the 3rd kinematics equation to get the exit velocity.
End Blog.
(Not too shabby for not remembering it until now, eh?)
- Turned in: Nothing
- Returned: Energy test
- Assignments made: Finish Crazy Coasters calculations (Plus working on your group's windmill or Rube Goldberg machine)
Detailed stuff:
I walked into my second class period on this fine February the 16th of the year 2012 thinking about how I was going to prepare for yet another gathering-info-to-write-my-blog-with session. Then I forgot all about it two seconds later.
No matter. My memory will serve me well.
So on that fine, fine day, after my short term memory threw out the thoughts of my blog, we picked up our Energy Test from our folders.
We began the class period with Coats-Haan and Mr. Ebersole asking us what were some good ways and bad ways of measuring the exit velocity of the marble as it left our rollercoasters. Two good ways were to use one of the photogates around the room (which Coats-Haan shows us how to use) and to measure it using the 3rd kinematics equation and the distance that the marble travels from being ejected at table height until it hits the ground. (I detail both of the good methods in my answer to the QotD.) One of the bad ways included using timers because they would be unreliable due to the great amount of human error involved in stopping and starting the them. Using Ui + Ki = Uf + Kf could also be considered a bad way because even though it gives a ballpark exit velocity, it does not take friction into consideration.
Afterwards, Mr. Ebersole dismissed us from our tables so we could continue working on our ever-so-innovative rollercoasters and so we could experimentally measure the exit velocity using the two good methods.
Matt's group had to finish putting their through-the-cardboard rollercoaster together. It was actually beginning to look sort of bulky and intimidating with all the tubing and double cardboard panels everywhere. It was like a Franken-coaster. However, Coats-Haan and Mr. Ebersole did say that many other groups throughout the day were copying their raging through-the-cardboard design. Good for them, setting precedents and whatnot.
Back at our overly duck-taped, one-loop wonder, Trevor, Chris, Aimee and I went straight for the photogate at the end of the room to measure our exit velocity. It took us a while, though. Sometimes, because the beginning of our track was so steep, the marble would not land on the track until a second or two later and the marble would have an usually slow exit velocity from not being able to pick up the full speed from the tubing. Much of our time was spent stacking and removing Chris' folders and trying to get the photogate to sense that the marble was passing through it. Late we realized that the marble was simply shooting out a little too high for the photogate to sense it, and we all mentally smacked ourselves in the faces.
Measuring with the 3rd kinematics equation method was a little more eventful. We propped our rollercoaster board up on top of Mr. Ebersole's table back by the AP lab, and after we measured the height of the table (0.8 m), we had a great time trying to see if the marble would land in the same spot every time (this is not a necessary step to finding the exit velocity). After our initial marble release, Chris put his eraser approximately where the marble landed (about .9 m away in the x-direction from the end of the rollercoaster) and we continued putting the marble through the coaster to see how often the marble would land in the area around the eraser.
To end the period, we relaxed and finished our final calculations on the Crazy Coasters worksheet.
Note: For #13, when you use the 3rd kinematics equation, use a height of 4 m instead of the 4.6 m (a measurement which has been wrong for years, apparently). The time you get as your answer in #13 will be used in the 3rd kinematics equation as well for #14.
Question of the Day:
Q: How do you measure exit velocity with the photogate timer? How do you measure it by projecting it off the table?
A: To measure exit velocity with the photogate timer, you take the diameter of the ball and divide it by the change in time from the moment the ball entered the photogate to the moment it left the photogate.
To measure the exit velocity by projecting the ball off the table, you use the 3rd kinematics equation for the motion in the y-direction to solve for the time it takes to touch the ground. You then take the distance in the x-direction that the ball traveled and divide it by the time you found using the 3rd kinematics equation to get the exit velocity.
End Blog.
(Not too shabby for not remembering it until now, eh?)
Thursday, February 16, 2012
2/16 qod
How do you measure exit velocity with the photogate timer? How do you measure it by projecting it off the table?
--ch
--ch
Wednesday, February 15, 2012
2/15 Tamayo
Question of the day. What is the normal force at the top of a roller coaster loop if you are just on the verge of falling off?
The normal force would be close to zero. The normal force is greatest at the bottom of the loop and least at the top of the loop. The motion of the car keeps it from falling down so if it were on the verge of falling off the normal force would be nearing zero, once the car detaches from the track the normal force from the track can no longer act on the car.
Coats-Haan was not here for second period today in Physics. Mr. Ebersole led us in today’s activities. We first turned in Desperado Redesign, if we didn’t turn it in on Tuesday. If we turned it in on Tuesday then, it was in our folders. We then looked at page 139-140 Crazy Coasters. This lab is completed with the people at our tables. This lab is quite exciting. First we had to complete questions 1-6 then we were able to start the building process. This lab consists of creating a rollercoaster for a marble. We then have to calculate where the marble will land. We worked on this for the entire day and we will have tomorrow as well. The coasters will be tested on Tuesday after the long weekend. Mr. Ebersole did warn us that if we leave the room with the marble then we will lose a lot of points on this lab for our group. This concludes our activities today in second period Physics.
Turned In: Desperado Redesign (if not turned in on Tuesday)
Got Back: Desperado Redesign (if turned in on Tuesday)
Homework: No homework!(Windmill Projects)
2/15 qod
What is the normal force at the top of a roller coaster loop if you are just on the verge of falling off?
--ch
--ch
Tuesday, February 14, 2012
Monday, February 13, 2012
2/13 Shah
Today in 1960, France Sahara desert. However, in our Physics class, we started class by finishing the video, and then we changed gears into our lab manual. We worked on pages 131 onwards, which dealt with roller coasters. We discussed multiple errors in various structures and methods to prevent those errors, followed by a reading and questions to accompany it. There were a few math problems related to that which we worked on in the end. We were running out of time so Coats-Haan took over and quickly finished the problem since we were running out of time. Homework is to finish number 10 and 11 from that assignment. We had nothing to turn in from the weekend as we spend Friday watching the roller coaster video. However, in our folders we got our test review and lab report back. Question of the Day: the normal force at the top of a roller coaster, if the passengers are just at the verge of falling off, is equal to the gravitational force, and thus F=mg.
2/13 qod
What is the normal force at the top of a roller coaster, if the passengers are just at the verge of falling off?
--ch
--ch
Sunday, February 12, 2012
2/12 Scheitlin
In physics class on Friday we watched a very interesting video on roller coasters. Before the video we were asked to fill out the before true/false questions on Extreme Machines Roller Coasters found on page 129 of your lab manual. The video took up the entire class time and Coats-Haan promised us that the video was rated PG, but I am not sure on that one. It was also hard not to laugh during the video, especially with the contagious laughter of Alexis. Overall it was a very relaxing class and if you did not turn in the worksheet on the video on Friday then you can turn it in on Monday, otherwise there is no homework due on Monday.
Question of the Day: Explain the g forces you experience on a roller coaster- well the g forces on roller coasters usually vary between +4 and -1/2. The more positive g's are experienced at the bottom of a drop.When accelerating downward you experience less positive g's which make you feel weightless and when accelerating up a steep hill you will feel heavier than normal because of the extra positive g's.
Question of the Day: Explain the g forces you experience on a roller coaster- well the g forces on roller coasters usually vary between +4 and -1/2. The more positive g's are experienced at the bottom of a drop.When accelerating downward you experience less positive g's which make you feel weightless and when accelerating up a steep hill you will feel heavier than normal because of the extra positive g's.
Friday, February 10, 2012
Thursday, February 9, 2012
Wednesday, February 8, 2012
2/08/2012 Nyaega
We began our wonderful Wednesday morning second period physics class by retrieving our Energy Practice Problems (which were also the previous nights homework) and using keys that were placed on our desks to check over our work. We were also given this time to work on our Energy test review guide. We were instructed to ask questions concerning, not only the review guide and energy practice problems, but on the whole unit in general for that was the last time (before the test) that questions could be asked. Various questions were indeed asked, some coming from Emily, others from Ethan and many more. The purpose of today's class was to prepare for our test and not much else was done.
Question of the day: How does the height that a pendulum rises to relate to the maximum angle that it makes with the vertical?
The angle made when it's at its maximum determines the height by the fact that the height is equal to the length of the string - length * cos of the angle.
Question of the day: How does the height that a pendulum rises to relate to the maximum angle that it makes with the vertical?
The angle made when it's at its maximum determines the height by the fact that the height is equal to the length of the string - length * cos of the angle.
2/8 qod
How does the height that a pendulum rises to relate to the maximum angle that it makes with the vertical?
--ch
--ch
Tuesday, February 7, 2012
2/7 qod
Give an example of a conservation of energy problem that has spring potential, gravitational potential, and kinetic energy.
--ch
--ch
Monday, February 6, 2012
02/06 Miley
To begin our marvelous Monday we checked our homework from the weekend, which was pg. 192 #55-60. After Mr. Ebersole helped clear up any confusion from the homework and discussed Superbowl commercials with us we began the Spring POGIL. This POGIL can be found on pgs. 118 and 119 of the lab manual. This POGIL helped us in learning how springs do work and how to measure this. Because the POGIL took longer than expected, it became part of our homework in addition to pg. 193 #63-67, the Home Energy survey, and the lab report for Conservation of Energy with Hall’s Carriage due on Wednesday.
QOD: Why is the definition of “work = Force x Distance” not always true?
I believe it is not always true because more than one force, like resistance or friction or gravity, may be acting on the object and impact the amount of work being done. Though I am not sure this is correct I drew my conclusion from # 60 on the pg. 192 homework.
Friday, February 3, 2012
Thursday, February 2, 2012
leonow 2/2/12
Today, we started off class by going over the arduous 25 problem homework about conservation of energy. Mrs. Coats-Haan praised our class for standing out among the other Honors Physics classes in work ethic, especially on our recent ticker tape lab. Then we worked on a lab called the Conservation of Energy with Hall's Carriage. It can be found on page 125 of the lab manual. This lab report is due 2/8/12 and the only homework for tonight is to work on the online simulation due tomorrow as well as the home energy survey.
The answer to the question of the day is final kinetic and potential energy can equal zero when the height is zero and when the moving object moves across a surface with great friction, causing it to slow to a stop by the work done by friction.
The answer to the question of the day is final kinetic and potential energy can equal zero when the height is zero and when the moving object moves across a surface with great friction, causing it to slow to a stop by the work done by friction.
2/2 qod
Give an example of using the Ui+Ki+W=Uf+Kf equation where the right side would all be zero.
-ch
-ch
Wednesday, February 1, 2012
2/1 qod
Happy February!
Give an example of when the work term in the conservation of energy would be positive and when it would be negative.
--ch
Tuesday, January 31, 2012
Monday, January 30, 2012
Friday, January 27, 2012
11/27 qod
How would you use the work energy theorem to calculate the work done in stopping a car tht was initially traveling 70 mph?
--ch
--ch
Thursday, January 26, 2012
1/26 qod
What did you think was the most difficult question on the quarter test? Why did you think it was difficult?
--ch
--ch
Wednesday, January 25, 2012
Chao 1/25
18 days until I can finally gain some freedom with an automobile license. The countdown has officially begun.
Moving on, today in Physics, we had a very interesting, hands-on day. We continued to finish up the little energy labs and stations that Coats-Haan set up around the room. I had to sport goggles because those green, cool glasses were not suitable for another pair of glasses that I have to mandatorily wear on my face. I felt quite sad looking like the average Chemistry student with goggle marks deeply embedded within my forehead.
Groups straddled from table to table, shaking plastics cans of sand, bending wire back and forth, spinning rotors with just two sticks, making matchstick rockets, and testing to see if lemons can really light up your home, among 14 different stations. We slowly filled out the worksheets regarding these energy labs from our lab manual. I believe it is page 107.
But sadly, all of the fun came to an end at 9:15 when the bell rang. If you didn’t finish getting your energy labs done, instructions are to complete the two worksheets on your own.
Additional homework, which is important to complete, is the 6.1 and 6.2 Guided Reading. A book, a pencil, and Internet access is needed. Oh, and a brain might be important too.
Question of the Day: What was your favorite station? What were the energy transformations at that station?
The station that I found to be my favorite was the station with the candles. After lighting a match and lighting a candle, we blew the candle out and immediately stuck the lit match into the smoke streak, which relit the candle! It was very cool.
The energy transformation that occurred at that station, I think, was thermal energy (caused from the friction of the match rubbing onto the box to ignite) converting to light energy (the flame). When the match was stuck onto the candle, I suppose the potential energy of the candle wick converted to thermal energy and light energy when the flame was brought to it. I’m not sure though.
Tuesday, January 24, 2012
1/24 qod
The dial on the far right of an electric meter reads 9. The dial next to it appears to be just on the 8. Is its value 7, 8 or 9? Justify your answer.
--ch
--ch
Armour 1/23
Today in physics we did multiple activities. The first thing we did was we viewed the new blog schedule. Next we were given our team farewells and a new blue make up policy sheet. After we filled out the farewells and gave them back to the appropriate person, we changed seats. Then Coats-Haan went over the new project where we have a choice to build a windmill or construct a Rube Goldberg machine. Lastly we made towers out of paper with one sheet of white paper and glue. Trevor Harrison’s group had the highest tower with 77.5 cm.
Q.O.D. What has to happen for you to do work?
There must be a displacement and a force must cause the displacement.