Question

The clouds remain suspended in the sky due to:
(A) Viscosity of air
(B) Viscosity of water in the cloud
(C) Negligible weight of cloud
(D) Sun’s gravitational force on cloud

Answer 1

Hint:A cloud is a mass of water drops or ice crystals suspended in the atmosphere. Clouds form when water condenses in the sky. Water vapour is always in the sky in some amount but is invisible. Clouds form when an area of air becomes cool enough for the water vapours to condense to liquid form. The condensation lets us see the water vapour.

Complete step by step solution:
Clouds mainly consist of small water droplets and ice crystals. The vast majority of clouds you see contain droplets and/or crystals that are too small to have any appreciable fall velocity, so the particles continue to float with the surrounding air. Upward vertical motions in the atmosphere also help the floating of clouds by balancing the fall velocities of their constituent particles. Clouds generally form, survive and grow in the air that is moving upward. Even though clouds contain a lot of water, the clouds have giant volumes which counter the effect of gravity on them and the water droplets.

Hence we can say that negligible weight and the high volume of the clouds keep them suspended in the air.

Therefore, option (C) is the correct answer.

Note:Clouds are important for many reasons like precipitation in the form of rain and snow. At night, clouds reflect heat to the surface and keep it warmer. During the day, clouds help shade us from the sun and lower the surface temperature. Studying clouds helps us better understand the Earth's weather and climate. Saturn's moon Titan has clouds of methane and ethane. Jupiter has clouds made of ammonia.
You can always rule out options such as option (D) which do not make sense at all. We all know that the Sun's gravity will not affect a cloud in the earth’s atmosphere.