Truck cylinder, ideal gas law problem

AI Thread Summary
The discussion revolves around a problem involving a diesel engine cylinder, where air is compressed, and the final temperature and volume need to be determined. The initial conditions include a volume of 500 cm^3, a temperature of 30°C, and a pressure of 1.0 atm. The user successfully calculated the final temperature to be 1100°C but struggled to find the final volume. After some attempts, they resolved the volume using the work formula related to pressure and volume changes. The conversation highlights the application of the ideal gas law and work-energy principles in thermodynamics.
Flip18064
Messages
7
Reaction score
0

Homework Statement



One cylinder in the diesel engine of a truck has an initial volume of 500 cm^3. Air is admitted to the cylinder at 30 C and a pressure of 1.0 atm. The piston rod then does 450 J of work to rapidly compress the air. What is its final temperature? What is its final volume?

Homework Equations



PV = nRT
\Delta Eth = (5/2)nR\DeltaT

The Attempt at a Solution



I found the temperature using the second equation to be 1100 C which is right. However i cannot find the final volume for the life of me. I tried P\gamma - 1T-\gamma and use the final pressure to find the volume but that didn't seem to work. Is there another way to go about this?
 
Physics news on Phys.org
finally figured it out using the formula:

W = PV\gamma(Vf1-\gamma - Vi1-\gamma)/(1 - \gamma)
 
Kindly see the attached pdf. My attempt to solve it, is in it. I'm wondering if my solution is right. My idea is this: At any point of time, the ball may be assumed to be at an incline which is at an angle of θ(kindly see both the pics in the pdf file). The value of θ will continuously change and so will the value of friction. I'm not able to figure out, why my solution is wrong, if it is wrong .
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...

Similar threads

Back
Top