Today obviously was a very special day. Just look at the numbers. People screaming wishes and all that just proves it’s special. Well, today in physics was pretty special too.
Of course, with every special day, the beginning starts out slow, mundane, and routine. Checking the board, we held tight to our papers filled with homework problems (none of which were just old problems with altered numbers) and did not think about the number of trees (or saplings) we potentially affected by using the paper. Carbon graphite is virtually able to obtain anywhere so we didn’t think about that either. Actually, on second thought, it still takes certain requirements to obtain graphite. So we should probably be feeling a little guilty. But hey, it was for physics. A good purpose.
Coats-Haan with her efficiency maximizing at second period already had keys laid out on the desks for us. While checking our answers to page 127 #10 – 17 and musing over our pg. 73-4 and pair checks received back in our blue folders, Coats- Haan looked to see that we completed our homework (mine already littered with red pen corrections). She also remarked how she heard that Carlie was a talkative person despite her quietness in Physics (or was it her dreaming? I don’t remember. I need sleep.).
After a few questions and remarks and quiet murmurs and probably a few more rounds of “Baa Baa Black Sheep” in Coats-Haan’s head, we commenced with our special task of the day: doing a POGIL with our new groups! Sending a person from each group whose name was at the beginning of the alphabet to grab the folders, Coats-Haan instructed the rest of us to take out pages 80.1-80.6 in our lab manuel. 80.1-80.4 is our POGIL; 80.5-80.6 is a forces diagram worksheet that is homework. Don’t worry: the pages are not split up into 10ths of a normal piece of paper. Coats-Haan simply just added more pages to the lab manuel but could not change the page numbering.
The POGIL was about forces and how different types of forces act on an object. There’s gravity (which acts downward on an object), normal force (which is always perpendicular to the surface and upwards, only exerted if there is a surface beneath the object), tension (which is instigated when an object is hanging from a rope or string and is always oriented upwards), and friction (which is instigated by motion and acts in the direction opposite of the motion). Certain situations dictate when each force acts. For example, if an object is at rest and suspended, there is no normal force or friction acting upon it, only tension and gravity. On the other hand, if an object is sliding down an inclined plane, there's gravity acting straight downwards, normal force acting perpendicularly upward, and friction acting in the opposite direction.
Stop signs dotted the page as we worked our way through the POGIL, sorting disagreements on the direction of normal force and on the application of tension. At 9:13 exactly (I know, not 11:11, that would have been cool), Coats-Haan stopped us and went over 80.3, the page with all of the diagrams. We had to draw the forces that each object exerted. Halfway through explaining the diagrams, the bell suddenly rang, ending our special day with POGIL. Coats-Haan will finish explaining Monday. Still, do the homework. It’s important.
Question of the Day:
How is the normal force oriented to surfaces?
The normal force is oriented in a way that is always perpendicular to the direction of the surface and upwards, I believe. For a flat plane, the normal orientation is straight up, 90o, stock straight. For an inclined plane, the angle of the normal force is slightly different but still in the general upwards direction.
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