Register to reply

Thermodynamics Question

Share this thread:
satanic
#1
May4-11, 10:31 AM
P: 2
1. The problem statement, all variables and given/known data

A balloon has 0.310 mol of polyatomics gas, Initial volume 7500cm³ and temp 29 degrees C, gas first expands isobarically until volume double. Then expands adiabatiacally until temp returns to initial value, assume gas is ideal gas, C_p = 33.26 J/mol*K, gamma = 4/3.

What is the final volume V?


2. Relevant equations

I think I have to use
PV = nRT
T_1V_1^(gamma-1) = T_2V_2^(gamma-1)

3. The attempt at a solution

I've tried to find the temperature after it expands isobarically and use that as the T1 value, I think this is the only trouble I'm facing here, after that I can find V_2 and add all volumes together, please guide me on how to find T after the isobaric expansion.
Phys.Org News Partner Science news on Phys.org
'Office life' of bacteria may be their weak spot
Lunar explorers will walk at higher speeds than thought
Philips introduces BlueTouch, PulseRelief control for pain relief
Andrew Mason
#2
May5-11, 10:53 AM
Sci Advisor
HW Helper
P: 6,684
Quote Quote by satanic View Post
1. The problem statement, all variables and given/known data

A balloon has 0.310 mol of polyatomics gas, Initial volume 7500cm³ and temp 29 degrees C, gas first expands isobarically until volume double. Then expands adiabatiacally until temp returns to initial value, assume gas is ideal gas, C_p = 33.26 J/mol*K, gamma = 4/3.

What is the final volume V?


2. Relevant equations

I think I have to use
PV = nRT
T_1V_1^(gamma-1) = T_2V_2^(gamma-1)

3. The attempt at a solution

I've tried to find the temperature after it expands isobarically and use that as the T1 value, I think this is the only trouble I'm facing here, after that I can find V_2 and add all volumes together, please guide me on how to find T after the isobaric expansion.
I will assume this is an ideal gas. So PV=nRT which means that T = PV/nR. If P is constant ΔT = ΔV(P/nR). Remember T is in Kelvins so the initial temperature 29C is what in Kelvin?

AM
satanic
#3
May5-11, 11:32 AM
P: 2
I've actually solved it, thank you anyway


Register to reply

Related Discussions
Thermodynamics question General Engineering 5
Thermodynamics- Zemansky Heat and Thermodynamics book question Advanced Physics Homework 0
Thermodynamics question please help Introductory Physics Homework 1
Thermodynamics question Advanced Physics Homework 7
Help with thermodynamics question please Introductory Physics Homework 3