A small drop of water falls from rest through | vedclass

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(D) When a small drop falls through a viscous medium like air,it experiences three forces: gravitational force acting downwards,and buoyant force and

Vedclass · Accepted Answer

Almost independent of $h$

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(D) When a small drop falls through a viscous medium like air,it experiences three forces: gravitational force acting downwards,and buoyant force and viscous drag acting upwards.As the velocity of the drop increases,the viscous drag force increases.Eventually,the net force on the drop becomes zero when the viscous drag and buoyant force balance the gravitational force.At this point,the drop attains a constant velocity known as the terminal velocity,given by $v_t = \frac{2r^2(\rho - \sigma)g}{9\eta}$.Since this terminal velocity depends only on the properties of the fluid and the drop,and not on the height $h$ from which it falls (provided $h$ is large enough for the terminal velocity to be reached),the final velocity is almost independent of $h$.

$A$ small drop of water falls from rest through a large height $h$ in air; the final velocity is ................

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