Question

What is the source of kinetic energy of falling raindrops?

Answer 1

the source of energy energy of wearing crop is there be due to falls down the the raindrops gain kinetic energy when they are in the clouds they have potential energy but then when they are dropped and come towards the earth again the energy due to falling down which is called Kinetic energy

Answer 2

Raindrops get the K.E from the gravity.
In the sky , the water droplets are in frozen form and hence fall fown due to gravity.
By the friction of air , the frozen droplets heat up and become water.