Question

6 warm air rises because
a. it is more dense than the surrounding cooler air
b. it is less dense than the surrounding cooler air
c. it is equally as dense as the surrounding cooler air
d. none of the answers is correct

Explanation:

According to the principle of density and buoyancy, when air is heated, its molecules gain energy and move more vigorously, causing the air to expand. As a result, the same mass of air occupies a larger volume, making it less dense. Less - dense substances tend to rise in a fluid (in this case, the surrounding cooler air acts as the fluid). For example, in a hot - air balloon, heating the air inside makes it less dense than the outside air, causing the balloon to rise.

Answer:

B. it is less dense than the surrounding cooler air