Isothermal Expansion, No Calculus

AI Thread Summary
The discussion centers on calculating the work done on a gas during isothermal expansion, given specific pressure and volume conditions. The first law of thermodynamics and ideal gas laws are referenced, with the internal energy change identified as zero due to constant temperature. The participant expresses difficulty in calculating the work done on the gas, seeking clarification on the appropriate formula to use without calculus. They suggest using the formula W=PVln(V2/V1) as a direct result for the calculation. The conversation emphasizes understanding the relationships between work, heat, and internal energy in thermodynamic processes.
Alexandra_H
Messages
1
Reaction score
0

Homework Statement



"We have some gas in a container at high pressure. The volume of the container is 444 cm^3. The pressure of the gas is 2.52e5 Pa. We allow the gas to expand at constant temperature until its pressure equals atmospheric pressure, which is 0.857e5 Pa."

A. Find the work (J) done on the gas.
B. Find the change of internal energy (J) of the gas.
C. Find the amount of heat (J) done on the gas.

Homework Equations



First law of thermodynamics. Ideal gas laws.

The Attempt at a Solution



(A) is what I'm having trouble with. The class is not calculus-based. (B) is zero, and for (C), W = Q (appropriate signs, - and -, as they seem to be referencing the surroundings, not the gas itself)--easy enough, once I have A.

Thoughts?
Thanks!
 
Physics news on Phys.org
Since you can't use calculus to derive the formula, I think you'd just need to use the direct result:

W=PVln(V2/V1)
 
Thread 'Collision of a bullet on a rod-string system: query'
In this question, I have a question. I am NOT trying to solve it, but it is just a conceptual question. Consider the point on the rod, which connects the string and the rod. My question: just before and after the collision, is ANGULAR momentum CONSERVED about this point? Lets call the point which connects the string and rod as P. Why am I asking this? : it is clear from the scenario that the point of concern, which connects the string and the rod, moves in a circular path due to the string...
Back
Top