Question

which of the following is an effect of the high input of solar radiation along the equator throughout the year?
choose 1 answer
a high solar heat makes air less dense, and less dense air limits rainfall.
b high solar heat allows air to hold more water vapor, and vapor condenses into rain.
c high solar heat reduces the moisture content of the air, so it limits rainfall.
d high solar heat makes the air more dense, which sinks and causes rain.

Explanation:

• Option A: Less - dense air (due to heating) actually rises, and rising air is associated with cloud formation and rainfall, not limiting it. So this option is incorrect.
• Option B: High solar heat (high temperature) allows air to hold more water vapor. As the air rises (because it is heated and becomes less dense), it cools, and the water vapor condenses to form rain. This is in line with the process of convectional rainfall near the equator.
• Option C: High solar heat (high temperature) allows air to hold more moisture (not reduce it). So this option is wrong.
• Option D: High solar heat makes air less dense (by heating and expanding the air molecules), not more dense. So this option is incorrect.

Answer:

B. High solar heat allows air to hold more water vapor, and vapor condenses into rain.