Final answer:
The superheating process in a refrigeration cycle is influenced by the temperature difference between the medium being cooled and the refrigerant temperature rather than other factors like the head pressure or sub-cooling.
Step-by-step explanation:
The amount of evaporator surface required for superheating in a refrigeration cycle depends on the temperature difference between the medium being cooled and the refrigerant temperature. The refrigerant temperature plays a critical role, as it must be sufficient to absorb the heat from the medium and induce the phase change necessary for the refrigeration process. When the refrigerant passes through the evaporator, it absorbs heat and vaporizes. The superheating process then increases the temperature of this vapor beyond its saturation temperature, ensuring that no liquid refrigerant enters the compressor. This process is strongly influenced by the difference between the temperature of the media being cooled (such as the air inside a refrigerator) and the temperature of the refrigerant vapor. It is less dependent on factors such as the amount of sub-cooling or the temperature of the saturated liquid. The head pressure of the system determines the temperature at which the refrigerant condenses, which is different from the superheating process in the evaporator.