Technician A says that the freezing point of a substance is the temperature at which the substance changes state from a solid to a liquid. Technician B says that the freezing point of a substance is the temperature at which the substance changes state from a liquid to a solid. Which technician is correct?
a) technician A
b) technician B
c) both technician A and B
d) neither technician A nor B

Technician B is correct

Explanation:

Freezing is a method of conversion of substance in its liquid state to solid state. It is the process by which a liquid substance changes to a solid at a particular temperature.

Increasing the pressure and decreasing the temperature of a liquid increases its freezing point. For example, in other to freeze water i.e to change water to ice, it has to be kept in a fridge at a temperature lower than the temperature of the water. The essence of covering the fridge after placing the water in the fridge is to increase the pressure of the liquid hence increasing its freezing rate.

Based on the above explanation, it can be concluded that technician B is correct.

we need to know the time interval during which the force acts. impulse of force = momentum change