Select the Kelvin-Plank statement of the second law:
According to the Clausius statement of the second law:
1. heat flows from cold surface to hot surface, unaided.
2. heat flows from hot surface to cold surface, unaided.
3. heat can flow from cold surface to hot surface with the aid of external work
Which of the above statements is/are correct?
If a heat engine attains 100% thermal efficiency, it violates
Such a heat engine is PMM2 which is impossible. It violates kelvin-Plank statement
A refrigerator and a heat pump operate between the same temperature limits. If the COP of the refrigerator is 4, the COP of the heat pump would be
If the temperature of the source is increased keeping sink temperature fixed, the efficiency of the Carnot engine
The more effective way of increasing the efficiency of a Carnot engine is to
(decreasing lower temperature by ΔT)
(increasing higher temperature by ΔT)
So, the more effective way to increase the cycle efficiency is to decrease lower temperature.
A Carnot engine operates between reservoirs at 20°C and 200°C. If 10 kW of power is produced, the rejected heat rate is nearest
An inventor invents a thermal engine that operates between ocean layers at 27°C and 10°C. It produces 10 kW and discharges 9900 kJ/min of heat. Such an enigne is
Actual efficiency is more than the 2nd law efficiency which is impossible.
If the time taken by a system to execute a process through a finite gradient is infinitely large, the process
“Heat cannot be transported from a system at low temperature to another system at high temperature without the aid of external agency”. This statement of second law is attributed to