Two students attended my session. There was a homework problem asking the change in momentum of a group of bullets striking a wall, aimed at helping students understand the kinetic theory of gases. Both students were having trouble with the problem. Their algebra was correct, but they were entering a positive momentum change. Once they realized that moving -> stopped was a negative change in momentum, lon capa accepted their answer.
There was a problem involving rescaling of the AMU. Both students were struggling, and I presented the problem as a unit conversion, as both students were familiar from general chemistry. This was enough for one student to solve the problem, but it remained abstract to the other. I was unable to make it fully clear to her, but she was confident she would be able to solve it on her own given that hint.
One of the students was struggling with adiabatic gas expansion. She was unfamiliar with the formula PV^gamma..., and after being shown this, she noted that the ideal gas law would follow, and was confident she could solve it on her own.
1/20,1/26,1/27.
No students attended my sessions on these dates. Homework was due 1/19 and there was an exam 1/29, and no students produced textbook questions in that time.
2/2:
There was a student struggling with a problem involving the electric force between two balls suspended from the ceiling. I suggested that he break the string tension into its x- and y-components and this made the concept clear to him. I did the writing on the whiteboard, so I hope I did not give too many hints, but I believe he solved the problem on his own past that point.
There was also a 0174 student struggling with his some concepts in Newton's Laws. Particularly, there was a problem with a rope hanging over a tree limb, with a monkey and box on either side. The problem was asking the acceleration with which the monkey would have to climb to lift the box from the ground. I suggested that the student reduced the monkey (and all other potential force generators) to boxes on a force diagram. This problem was still intuitively abstract to him (and me), but this method generated the correct answer as a proof of the method for simplifying the problem.
With that same 0174 student, we went over a problem with boxes on slants, connected by a pulley. He wanted to simplify the problem into "cookbook" type solutions he could remember for the future. I tried to convince him that it was an unreliable strategy in physics, but I did not get the impression that he believed me. As the course progresses, I'm hopeful he will try to slow down his approach.
2/3:
A 0110 student came to the session unsure
how to solve the problem in which two projectiles were approaching each other
in 1D. I asked the student to write out all of her known variables, and the value
she was looking for (time). Once she did that, she was better able to visualize
the problem and solved it on her own.
Corey Williams
Physics 0111 (Dr. Lynch)
Took 174/175.
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