Question in first pic and solutions in 2&3
1)My question is here we are calculating efficiency of what because the efficiency of Carnot's engine is coming simply 0.69
2) Question from 2nd pic how in Physics we take time as 1 like here taken W=Px1 ,for making P=W otherwise they are not equal
3) Question from 3rd pic how u make 40 K watt to 40 KJ by using 4 cycles in 1 sec??