Question

Skating on ice is possible because of the phenomenon of
A. Friction.
B. Sublimation.
C. Regelation.
D. Latent heat of fusion

Answer 1

Hint: If we need to skate on ice, we need to form gaps on the smooth surface of ice by converting it to water. Water can also help as lubricant for movement. So, we need to lower the freezing point of water. This conversion of ice into water by application of external force makes it possible to skate on ice.

Complete step by step answer:
We must know that the process of formation of water due to increase in pressure is known as regelation. By this phenomenon we are lowering the freezing point of water by application of pressure. We can define regelation as the phenomenon in which at below temperature, on the application of pressure the ice melts to water and on the removal of this pressure, it refreezes back to ice. We can demonstrate this process by compressing the ice and turning it to water, and when this pressure is removed it solidifies again. This means that a liquid changes into solid when pressure and energy are released, freezing is always an exothermic process.

So, if we take the case of skating, we are applying pressure on the ice with skating blades, the ice will turn to water wherever we are applying pressure and this water formed will act as lubricant of smooth movement of the blades through ice. So, we can conclude that regelation is the process which helps for skating on ice.
Hence, the correct answer is option C.

Note:
We should be aware that the process of regelation also helps in many other cases. For example, glaciers which act as a source of river due to regelation. Here, the mass of the glacier exert pressure on the ice at its base and turns it to water. Also, we can make ice balls by application of pressure.