How Is Work Done by Gas Calculated in a Thermodynamic System?

  • Thread starter Thread starter LostTexan07
  • Start date Start date
  • Tags Tags
    Gas Thermodynamics
AI Thread Summary
In a thermodynamic system with a gas in a cylinder and a frictionless piston, 1400 kcal of heat is added, causing the volume to increase from 12.0 m³ to 17.7 m³. To calculate the work done by the gas, the equation W = PΔV is used, where P is the atmospheric pressure and ΔV is the change in volume. The change in internal energy (ΔU) can be calculated using the equation ΔU = Q - W, where Q is the heat added. The challenge arises from needing to convert kcal to joules and determining the pressure to find the work done. The discussion highlights the importance of understanding the relationship between heat, work, and internal energy in thermodynamic processes.
LostTexan07
Messages
3
Reaction score
0

Homework Statement


A gas is enclosed in a cylinder fitted with a light frictionless piston and maintained at atmospheric pressure. When 1400 kcal of heat is added to the gas, the volume is observed to increase slowly from 12.0 m3 to 17.7 m3. Calculate the following
(a) work done by the gas ____ J
(b) change in internal energy of the gas ____ J

Homework Equations


(delta)U = Q - W


The Attempt at a Solution


I tried to convert 1400 kcal to J and plug it into the problem, but it appears that I have two unknown variables and I'm not really sure where to go from here.
 
Physics news on Phys.org
The work on a isobaric process (since the piston is free to move without friction) is given by the equation W = P.\DeltaV
 
Thread 'Voltmeter readings for this circuit with switches'
TL;DR Summary: I would like to know the voltmeter readings on the two resistors separately in the picture in the following cases , When one of the keys is closed When both of them are opened (Knowing that the battery has negligible internal resistance) My thoughts for the first case , one of them must be 12 volt while the other is 0 The second case we'll I think both voltmeter readings should be 12 volt since they are both parallel to the battery and they involve the key within what the...
Thread 'Correct statement about a reservoir with an outlet pipe'
The answer to this question is statements (ii) and (iv) are correct. (i) This is FALSE because the speed of water in the tap is greater than speed at the water surface (ii) I don't even understand this statement. What does the "seal" part have to do with water flowing out? Won't the water still flow out through the tap until the tank is empty whether the reservoir is sealed or not? (iii) In my opinion, this statement would be correct. Increasing the gravitational potential energy of the...
Back
Top