A raindrop falls near the surface of the earth with almost uniform velocity because
(a) its weight is negligible
(b) the force of surface tension balances its weight
(c) the force of viscosity of air balance its weight
(d) the drops are charged and atmospheric electric field balances its weight.
Answers
Answered by
3
A raindrop falls near the surface of the earth with almost uniform velocity because the force of viscosity of air balance its weight. Option C is correct.
Explanation:
1. When raindrop fall in surface of earth. There are two force which act on raindrop.
2. First force is gravitational force by earth. Second force is viscous force by air.
3. Gravitational force act in downward direction. Viscous force act in upward direction.
4. So net force = Gravitational force - viscous force. But near to earth surface gravitational force is equal to viscous force.
5. So net force on raindrop is zero. In case of when net force on object is zero, object is moving with constant velocity.
This is reason of raindrop move with constant velocity due to net force on raindrop is zero.
Answered by
3
VISCOSITY BALANCES WEIGHT
Explanation:
Correct Answer is (c)
We know that,
- Air has viscosity.
- During rainfall, the raindrops acquire acceleration due to gravity.
- However, the increase in velocity is hindered by viscous force acting upwards.
- And a gradual balance between the two opposing forces causes the raindrops to attain a terminal velocity, thus, falling with a uniform velocity.
Similar questions