Why are dewdrops not formed on a cloudy night?

  1. Clouds absorb the radiation released from the Earth's surface.
  2. Clouds reflect back the Earth's radiation.
  3. The Earth's surface would have low temperature on cloudy nights.
  4. Clouds deflect the blowing wind to ground level.


Because on a cloudy night, the clouds send the heat back to the ground so the ground never gets cold enough for the dew to be formed. Dew drops are formed due to condensation of water vapours. Air around us contains water vapours which we call moisture or humidity.

Hot air contains more moisture as compared to cold air. During the night when the hot air comes into contact with some cold surface due to the reflection of earth radiation by clouds, water vapour present in it condenses on the cold surface in the form of droplets. These tiny drops of water are called dew drops.

The correct option is B.