Question

what causes the greenhouse effect?
a. earth radiates mostly visible light.
b. earth radiates mostly infrared light.
c. visible light can escape the atmosphere.
d. ultraviolet light cannot transmit through the atmosphere.

Explanation:

The greenhouse effect occurs because certain gases in the Earth's atmosphere (like carbon dioxide) trap heat. The Earth absorbs visible light from the sun and then radiates heat. This heat is in the form of infrared light. Greenhouse gases absorb and re - radiate infrared light, keeping the Earth warm.

• Option A: Earth does not radiate mostly visible light. It absorbs visible light (from the sun) and radiates infrared light.
• Option C: While visible light can pass through the atmosphere (which is how it reaches the Earth from the sun), this is not the cause of the greenhouse effect. The greenhouse effect is about the trapping of infrared radiation.
• Option D: Ultraviolet light is mostly absorbed by the ozone layer. But this has nothing to do with the greenhouse effect mechanism which is centered around infrared radiation.

Answer:

B. Earth radiates mostly infrared light.