Question

Assertion [A]: Greenhouse effect is due to a layer of CO₂ in the atmosphere.

Reason [R]: The glass panels of a greenhouse allow sunlight to pass through but prevent heat from being re-radiated into outer space.

• A. Both A and R are true and R is the correct explanation of A
• B. Both A and R are true but R is not the correct explanation of A
• C. A is true but R is false
• D. Both A and R are false

Answer 1

The correct option is B Both A and R are true but R is not the correct explanation of A

$\bullet$ A greenhouse allows the sunlight to pass through. It traps the heat inside and does not allow the heat to escape out.

$\bullet$ CO₂ in the troposphere behaves like glass panels of a greenhouse allowing the sunlight to pass through, but preventing the heat from being re-radiated into outer space.

$\bullet$ During day time, Earth's surface warms up and at night, Earth's surface cools down, releasing the heat back into the air.

$\bullet$ But, some of the heat is trapped by the greenhouse gases (especially carbon dioxide and water vapour). This prevent the heat from escaping into outer space.