Answer:
Energy used = 4KJ
Explanation:
Second law of thermodynamics states that as energy is transferred or transformed, more and more of it is wasted. The Second Law also states that there is a natural tendency of any isolated system to degenerate into a more disordered state.
Now when we apply that to heat engines, we'll see that;
Heat expelled = Heat removed + Work Done
We can write it as;
Q_h = Q_c + W
We are given that;
Heat removed; Q_c = 20KJ
Heat expelled into the room in each cycle; Q_h = 24KJ
Thus; plugging these 2 values into the equation, we obtain;
24 = 20 + W
W = 24 - 20
W = 4 KJ
Work done is energy used.
Thus, energy used = 4 KJ
