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

A cylinder is equipped with a smoothly movable piston which is connected by a spring to the bottom of the cylinder as shown in the figure. An ideal gas of 0.1 mol is confined in the space on the left side of the cylinder at a temperature of 300 K. The atmospheric pressure is 1 x 10^{5}Pa. Take the cross-section area of the piston to be 1 x 10^{-3}m^{2}, the spring constant to be 500 N/m and the gas constant to be 8.3 J / mol K

1. Initially the spring is at its natural length. Calculate the volume of the gas

By heating the gas, the piston moves to the right a distance of 0.2 m

2. Calculate the pressure of the gas after the change

3. Calculate the temperature of the gas after the change

4. Calculate the work done by the gas during the change

2. Relevant equations

W = p ΔV

PV / T = constant

F = kx

W = 1/2 kx^{2}

3. The attempt at a solution

1. done (ans = 2.5 x 10^{-3}m^{3})

2.

P = F/A = kx/A = (500) (0.2)/(1 x 10^{-3}) = 1 x 10^{5}Pa

but the answer is 2 x 10^{5}Pa.

So should it be the initial pressure + P = 1 x 10^{5}Pa + 1 x 10^{5}Pa = 2 x 10^{5}Pa ??

3. no problem if (2) done

4. work done = 1/2 kx^{2}= 1/2 (500) (0.2)^{2}= 10 J

but the answer is 30 J...don't know what to do and why I was wrong...

thanks

**Physics Forums | Science Articles, Homework Help, Discussion**

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Homework Help: Piston with string

**Physics Forums | Science Articles, Homework Help, Discussion**