Thermodynamics (Physics)

As shown in the figure, five Carnot engines, each with efficiency and same number of cycles per unit time, are operating between six heat reservoirs. The amount of heat released per cycle by one engine is completely absorbed by the next engine. Consider Q0 to be the amount of heat absorbed per cycle by the first engine and W as the amount of total work done by all the engines per cycle, then the net efficiency of the system is found to be net = WQ0 = 211243. The value of is: [figure]

The efficiency of a Carnot engine operating with a hot reservoir kept at a temperature of 1000 K is 0.4. It extracts 150 J of heat per cycle from the hot reservoir. The work extracted from this engine is being fully used to run a heat pump which has a coefficient of performance 10. The hot reservoir of the heat pump is at a temperature of 300 K. Which of the following statements is/are correct:

1. Work extracted from the Carnot engine in one cycle is 60 J.
2. Temperature of the cold reservoir of the Carnot engine is 600 K.
3. Temperature of the cold reservoir of the heat pump is 270 K.
4. Heat supplied to the hot reservoir of the heat pump in one cycle is 540 J.