Question

Which of the following describes the relationship correctly?

A.Air expands, becomes less dense, and rises.
B. Air expands, becomes denser, and sinks.
C. Air contracts, becomes denser, and rises.
D. Air contracts, becomes less dense, and sinks.

Answer 1

A. Air expands, becomes less dense and rises when the temperature is high due to the increased kinetic energy. This causes the air molecules to move around much more so they are further apart.

Answer 2

Answer: Option (A) is the correct answer.

Step-by-step explanation:

Density is defined as the degree of compactness or mass per unit volume of a substance.

When air expands then it means its molecules have gained kinetic energy. Therefore, they are colliding with each other and result in expansion of air.

So, expansion makes air less dense as mass per unit volume decreases on expansion. Therefore, air rises on expansion.

Thus, we can conclude that air expands, becomes less dense, and rises describes the relationship correctly.