Question

please answer these questions

1. What is the difference between a refrigerator and a heat pump?
2. A heat pump and a refrigerator are operating between the same two thermal
reservoirs. Which one has a higher COP?
3. Define the COP of a heat pump.
4. Thermal efficiency of a heat engine is defined to be the ratio of energy output
desirable to energy input. Would you think that efficiency is an appropriate definition
to be used when a heat pump is being discussed? Why?
5. Is the COP of a heat pump always larger than 1?
6. Indicate whether the following statements are true or false:
7. A process that causes heat to be removed from one reservoir only is feasible.
8. A process that causes heat to be supplied to one reservoir only is feasible.
9. A process that causes heat to be transferred from reservoir A to reservoir B is feasible.
10. For a heat pump, COP<1.
11. For a refrigerator, COP<1

Answer 1

ANSWER HEAT ENGINE REFRIGERATOR a) In a heat erginea) A refrigerator is a heat is transferred reversed heat engine. from a higher temperat b) Heat is transferred from ture level called source lower temperature level to to a lower temperafore higher temperature by called Sink applying external work b) work is obtained to maintain the temperature during this process I below atmospheric temperatore e) The working temperature umpica are of c) The working temperar ture in a refrigerator are of colder level and atmosphere. hotter level and atmosphere If the heat purnp and refrigerator operates between same two thermal reserwours The (cop) Ref = (cop) up

cop of heafpump is greater compared to refrigerato- cop of heat pump. The coefficient of performance of a heatpump is a ratio of wseful healing prowided to work required cop= r Q. useful heat W = work required cop at where an Heat reserwower supplied to the hot Thermal efficiency of a heat engine is defined as useful work to heat input. yes the efficiency is an appropriate definition to be used because heat pumps are used to transport heat from a low temperačuve place to a hot temperature place in order to keep the hot place at a high temperature by applying work. So the effiuency in this Case is exerted to the hot place per unit of work.

we know that (copup · I+ (cop) Pop (cophop Reciprocal of efficiency. He And we know that efficiency is always less than I, so the reciprocal of efficrency is always greater than 1 Hence (cop) of heat pump is greater than I. FALSE FALSE 9 0 TRUE FALSE 9 TRUE