Internal Enery, heat and work/HELP

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The discussion revolves around a homework problem involving an ideal gas in a cylinder with a movable piston. The user has provided initial and final pressures and volumes, along with a heat transfer value, seeking help to find work done (W), change in internal energy (ΔU), and initial and final temperatures (Ti and Tf). The user calculated W as 200J and ΔU as 700J but is uncertain about their accuracy and how to determine the temperatures. A participant suggests using the ideal gas law (PV=nRT) to find the temperatures, emphasizing the need to clarify the relationship between work done and changes in internal energy. The conversation highlights the importance of understanding the equations connecting pressure, volume, and temperature for ideal gases.
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Homework Statement


There's .1 mole of an ideal gas trapped in a cylinder with a movable piston.
If Pi= Pf= 5000Pa, Vi= .04 m^3, Vf= .08m^3, Q=500J,,,Find W, change in (U), Ti and Tf.

Homework Equations



change in U = Q+W
W= -p change in V

The Attempt at a Solution



W= 200J
change in U = 700J
Ti=
Tf= i don't know how to get Ti and Tf... I am not sure whether 200J and 700J are right either..
PLease help me!
Thank you!
 
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You certainly know an equation connecting P, V and T for an ideal gas.

The gas expands, is the work done on the gas positive or negative? Will this work increase or decrase the internal energy?

ehild
 
PV=nRT

Could you please explain more in detail? I don't get what you're saying:(

THanks.
 
You know P, V, n for both states of the gas, don't you? Can you calculate the temperatures?

ehild
 
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