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Reynold's Number

When a sphere...

Question

When a sphere falling in a viscous fluid attains a terminal velocity, then:

A

the net force acting on the sphere is zero

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B

the drag force balances the buoyant force

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C

the drag force balances the weight of the sphere

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D

the buoyant force balances the weight and drag force

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Solution

The correct option is A the net force acting on the sphere is zero
Terminal velocity is said to be achieved when the body has attained equilibrium under gravity, buoyant and viscous forces, and velocity no more changes due to any acceleration.Here velocity is constant so accceleration of sphere is zero .

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