Dear Student
The water cycle is the movement of water between the Earth's surface, the sky and underground.
Water evaporates due to heat from the sun; it condenses in clouds and forms rain; the rain forms streams, rivers and other reservoirs which then evaporate again
In the water cycle, the heat and light of solar energy cause water to melt or evaporate, changing the water from a solid or liquid form to a vapor.
So Sun is main source of energy.
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