A system undergoes a two-step process. In the first step, the internal energy of the system increases by 368 J when 144 J of work is done on the system. In the second step, the internal energy of the system increases by 24 J when 248 J of work is done on the system.
(a) For the overall process, what is the heat?
J
(b) What type of process is the overall process?
Isobaric
Isochoric
Isothermal
Adiabatic
I'm confused to what do on the first part but I think from looking at the problem (b) would be adiabatic. I sthat correct? And please help with part (a)
To find the heat for the overall process, we can start by understanding the first law of thermodynamics, which states that the change in internal energy of a system is equal to the heat added to the system minus the work done by the system:
ΔU = Q - W
where ΔU is the change in internal energy, Q is the heat added to the system, and W is the work done by the system.
Here, in the first step, the internal energy increases by 368 J when 144 J of work is done on the system. Therefore, the change in internal energy for the first step is ΔU1 = 368 J and the work done by the system in the first step is W1 = -144 J (negative sign indicates work done on the system).
In the second step, the internal energy increases by 24 J when 248 J of work is done on the system. Thus, the change in internal energy for the second step is ΔU2 = 24 J and the work done by the system in the second step is W2 = -248 J.
To calculate the overall change in internal energy, we can sum up the changes in internal energy for each step:
ΔU = ΔU1 + ΔU2
ΔU = 368 J + 24 J
ΔU = 392 J
Now, we can find the overall heat by rearranging the first law of thermodynamics equation:
Q = ΔU + W
Q = 392 J + (-144 J + -248 J)
Q = 392 J - 392 J
Q = 0 J
Therefore, the heat for the overall process is 0 J. This indicates that no heat is added to or removed from the system during the process.
For part (b), to determine the type of process, you need additional information about the system. Adiabatic processes are those where no heat exchange occurs between the system and its surroundings. If the problem does not provide any information about heat exchange or the system being thermally insulated, it is not possible to determine the type of process with the given information.