The velocity of a small ball of mass 'm' and density d1, when dropped in a container filled with glycerin, becomes constant after some time. If the density of glycerin is d2, then the viscous force acting on the ball, will be :
Solution
<p>Viscous force acting on the ball will be equal and opposite to net of weight and buoyant force</p>
<p>$\Rightarrow {F_0} = {4 \over 3}\pi {r^3}{d_1}g - {4 \over 3}\pi {r^3}{d_2}g$</p>
<p>$= {4 \over 3}\pi {r^3}{d_1}g\left( {1 - {{{d_2}} \over {{d_1}}}} \right)$</p>
<p>$= mg\left( {1 - {{{d_2}} \over {{d_1}}}} \right)$</p>
About this question
Subject: Physics · Chapter: Properties of Solids and Liquids · Topic: Elasticity
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