(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Problem comes straight from a 2001 AP Physics B test

http://img151.imageshack.us/img151/6159/physicscylinderszq4.png [Broken]

2. Relevant equations

PV = nRT

KE = 3/2KT

deltaU = Q+W

3. The attempt at a solution

Okay, for the first two (a and b) I arrived at an answer ofdouble the initial pressure of State 1 and half of the initial volume of State 1.This was because after I drew myself a little P vs. V graph, I knew the two States had to be on the same isotherm, so pressure had to increase in order for volume to decrease. Also, I just realized as I write this, if T is constant, in PV = nRT that means nRT is a constant and as P increases, V must decrease.

I'm pretty sure that's right, if it's wrong, I would appreciate clarification.

ForcI gotIsobaric, simply because isothermal and adiabatic do not work.

FordI gotYes, 4 --> 1 is isobaricsimply because I drew a P versus V graph and since it has to go back to the same isotherm State 2 was on, but volume had to decrease, it had to be isobaric.

I do not understand e. I'm having a hardtime knowing what the weight does...do you have to use P = F/A?

Thanks for any help at all on this, any corrections if im wrong and any elaboration on any topic is greatly appreciated.

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# Volume and Pressure Cylinders

Can you offer guidance or do you also need help?

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