Consider a heat engine as shown in the figure. Q1andQ2 are heat added to T1 and heat taken from T2 respectively, in one cycle of the engine. W is the mechanical work done on the engine.

If W > 0, then possibilities are:

(a)Q1>Q2>0(b)Q2>Q1>0(c)Q2<Q1<0(d)Q1<0,Q2>0

Choose the correct alternatives:
1. (b, c)

2. (a, d)

3. (b, d)

4. (a, c)

(4) Hint: Use the concept of heat engine.
Step 1: Find the relation between W, Q1andQ2.
Considering the figure, we can write, Q1=W+Q2
W=Q1-Q2>0                      (By question)
Q1>Q2>0                (If both Q1andQ2 are positive)
We can also, write Q2<Q1<0   (If both Q1andQ2are negative)