Problems: Remember to show process on a p-v plot

Word Problem	(a) Find the change in specific internal energy (in kJ/kg) when an aluminum pie pan is heated from room temperature (68 degrees F) to 450 degrees F. (b) Find the change in specific internal energy (in kJ/kg) for a copper pot experiencing the same temperature change.
3.51
3.53
4.46
4.61
4.23 *	Look at it, but do not hand in.

Answers:

3.51:	1W2/m = - 2.368 kJ/kg 1Q2/m = - 20.21 kJ/kg
3.53:	1Q2/m = 5.36 kJ/kg
4.46:	Q-dot = - 6.45 kW
4.61:	delta-KE/m = 0.0752 kJ/kg Q-dot = 3.41 kW
4.23:	velocity2 = 664.1 m/s A1 = 0.0017 m2 A2 = 0.00062 m2

Hints:

3.51:	Draw process on a p-v plot
3.53:	Problem builds on 3.36. Be sure to find the phase at state 2.
4.46:	Be sure to find the phase at each state. Use the volumetric flow rate to find the MASS flow rate -- that's what is in the 1st law equation for open systems.
4.61:	W-dot = 0 for the pipe.

Please Remember:

• Read EACH word.
• Draw some pictures (one for each state, or of the device).
• Write the given information under each/the picture.
• Write what you know about the process.
• Write what it is you are to find.
• DRAW THE PROCESS ON A p-v PLOT (for closed system problems).
• Write write the equations you are to use (or might want to use).
• If necessary, find the phase at each state.
• Be sure to indicate which tables you are using.
• Be sure to use the proper "work equation" for you process.
• PLEASE try to be organized.