Explanation:

In a vapour compression refrigeration system, the working fluid is a refrigerant that undergoes a cyclic process consisting of four components, namely, an evaporator, a compressor, a condenser, and an expansion valve. The refrigerant flows through these components in a closed loop and undergoes phase changes from a low-pressure, low-temperature vapour to a high-pressure, high-temperature vapour and back to a low-pressure, low-temperature vapour.

Superheated Vapour:

A superheated vapour is a state where the refrigerant vapour has been heated above its saturation temperature at a given pressure. This means that the refrigerant is no longer saturated and contains energy in the form of sensible heat.

Entrance to Component:

The entrance to a component refers to the point at which the refrigerant enters the component. In the case of a vapour compression refrigeration system, the entrance to the components is critical in determining the state of the refrigerant and the performance of the system.

In a vapour compression refrigeration system, the working fluid enters the components in the following order:

1. Evaporator: The evaporator is the component where the refrigerant absorbs heat from the surrounding environment and evaporates into a low-pressure, low-temperature vapour. The refrigerant enters the evaporator as a low-pressure, low-temperature liquid.

2. Compressor: The compressor is the component where the refrigerant vapour is compressed to a high-pressure, high-temperature vapour. The refrigerant enters the compressor as a low-pressure, low-temperature vapour.

3. Condenser: The condenser is the component where the refrigerant gives up heat to the surrounding environment and condenses into a high-pressure, high-temperature liquid. The refrigerant enters the condenser as a high-pressure, high-temperature vapour.

4. Expansion Valve: The expansion valve is the component where the refrigerant undergoes a pressure drop and a corresponding decrease in temperature. The refrigerant enters the expansion valve as a high-pressure, high-temperature liquid.

Therefore, at the entrance to the condenser, the refrigerant is a superheated vapour because it has been compressed in the compressor and heated above its saturation temperature.