Question 608: Thermodynamics & KTG

Question

In the reported figure, heat energy absorbed by a system in going through a cyclic process is ___________ $$\pi$$J.

Accepted Answer

Consider the given diagram,
Here, r
1
= 10 $$	imes$$ 10
3
m and r
2
= 10 $$	imes$$ 10
-3
m
We know that for a complete cyclic process, change in internal energy, ($$\Delta$$U) = 0 .... (i)
According to 1st law of thermodynamics,
$$\Delta$$Q = $$\Delta$$U + W ..... (ii)
From Eqs. (i) and (ii), we get
$$\Rightarrow$$ $$\Delta$$Q = 0 + W
$$\Rightarrow$$ $$\Delta$$Q = W .... (iii)
$$\because$$ W = Area = $$\pi$$r
1
r
2
= $$\pi$$ $$	imes$$ (10 $$	imes$$ 10
3
) $$	imes$$ (10 $$	imes$$ 10
$$-$$3
)
W = 100 $$\pi$$ J .... (iv)
From Eqs. (iii) and (iv), we get
$$\Delta$$Q = 100 $$\pi$$ J

Thermodynamics & KTG

In the reported figure, heat energy absorbed by a system in going through a cyclic process is ___________ $\pi$J.

Choose the correct answer: