Question

When the bottom of a pan of water is heated, and the water expands, becoming less dense than the surrounding water, it is forced to rise. The water cools and sinks back to the bottom of the pan. This process is called what?

a. Conduction
b. Convection
c. Radiation
d. Evaporation

Answer 1

The process described is called convection, where the warmer material rises and the colder material sinks, transferring energy.

Step-by-step explanation:

The process described, in which the bottom of a pan of water is heated, causing the water to expand and become less dense than the surrounding water, is called convection. Convection is the heat transfer by the motion of matter, where the warmer material rises and the colder material sinks, transferring energy.

In this case, when the bottom of the pan is heated, the water near the bottom becomes warmer. As it heats up, it expands and becomes less dense, causing it to rise towards the top. As the water cools down, it becomes denser again and sinks back to the bottom, completing the convection cycle.

This process of convection plays an important role in heat transfer inside the pot of water, allowing the heat from the bottom to be distributed to other regions of the water.