Question

A monatomic ideal gas (n moles) undergoes this cycle: (1) starting at V1, T1, it increases the temperature at constant volume to 3T1; (2) from V1, 3T1, it increases the volume at constant temperature to 2V1; (3) from 2V1, 3T1, it decreases the temperature at constant volume back to the original temperature, T1; (4) from 2V1, T1, it decreases the volume back to the original volume, V1.

(a) Sketch the cycle on a P-V diagram.

(b) In terms of n and T1, what is the net work done by the game per cycle?

(c) What is the efficiency of the cycle?

Answer 1

p-v is shown in next figure

properties of different points are

point 1-

point 2-

point 3-

point 4-

(ii)for process 1-2 and 3-4 work done is done because constant volume process

other two processes are constant temp process

and

for monoatomic gas

so net W=17.288-5.763 joule

W= joule
(iii)efficiency=net heat produced/net work done

heat produced will be zero in process 2-3 and 4-1

for monoatomic gas

and for process 1-2 and 3-4 formula for heat  

so net heat=0

so efficiency=0