Answer:

Reversed Carnot cycle:

Reversed Carnot cycle is a thermodynamic cycle which consists of four reversible processes:
1. Isothermal expansion
2. Adiabatic expansion
3. Isothermal compression
4. Adiabatic compression

COP of a refrigerator:

Coefficient of Performance (COP) of a refrigerator is defined as the ratio of heat extracted from the refrigerated space to the work done by the compressor.

COP = Q2 / W

where, Q2 is the heat extracted from the refrigerated space and W is the work done by the compressor.

COP of a refrigerator working on reversed Carnot cycle is given by:

COP = T2 / (T2 - T1)

where, T1 and T2 are the temperatures at the evaporator and condenser respectively.

Given, COP = 4

So, T2 / (T2 - T1) = 4

T2 = 4T2 - 4T1

3T2 = 4T1

T2 / T1 = 4/3

So, the ratio of condenser and evaporator temperatures is 4/3.

Heat pump:

A heat pump is a device which extracts heat from a low-temperature source and transfers it to a high-temperature sink. The COP of a heat pump is defined as the ratio of heat transferred to the high-temperature sink to the work done by the compressor.

COP = Q1 / W

where, Q1 is the heat transferred to the high-temperature sink and W is the work done by the compressor.

Heating effect:

If the refrigerator works as a heat pump and consumes 1 kW of work, the heating effect will be:

COP = Q1 / W

Q1 = COP * W

Q1 = 4 * 1 kW

Q1 = 4 kW

So, the heating effect will be 4 kW.

Conclusion:

Hence, the heating effect of a refrigerator working on reversed Carnot cycle as a heat pump and consuming 1 kW of work will be 4 kW.