Why are dewdrops not formed on a cloudy night?
✓ Correct answer: b) Clouds reflect back the Earth’s radiation.
ExplanationDew formation occurs when the Earth’s surface cools down sufficiently at night, causing moisture in the air to con- dense into water droplets on cool surfaces.On clear nights, the Earth’s surface loses heat rapidly through a process called radia- tive cooling.This cooling lowers the temperature of surfaces like grass or leaves, leading to the formation of dew as the air reaches its dew point.Option (b) is correct : On cloudy nights, the situation changes.Clouds act like a blanket, reflecting back the infrared radiation (heat) emitted by the Earth’s surface.This process is known as the greenhouse effect at a smaller scale.Because the heat is trapped, the Earth’s surface doesn’t cool enough for dew to form.31
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