Question 122: Properties of Matter

Question

The velocity of a small ball of mass 'm' and density d
1
, when dropped in a container filled with glycerin, becomes constant after some time. If the density of glycerin is d
2
, then the viscous force acting on the ball, will be :

Accepted Answer

Viscous force acting on the ball will be equal and opposite to net of weight and buoyant force
$$ \Rightarrow {F_0} = {4 \over 3}\pi {r^3}{d_1}g - {4 \over 3}\pi {r^3}{d_2}g$$
$$ = {4 \over 3}\pi {r^3}{d_1}g\left( {1 - {{{d_2}} \over {{d_1}}}} \right)$$
$$ = mg\left( {1 - {{{d_2}} \over {{d_1}}}} \right)$$

Answer

$$mg\left( {1 - {{{d_1}} \over {{d_2}}}} \right)$$

Answer

$$mg\left( {1 - {{{d_2}} \over {{d_1}}}} \right)$$

Answer

$$mg\left( {{{{d_1}} \over {{d_2}}} - 1} \right)$$

Answer

$$mg\left( {{{{d_2}} \over {{d_1}}} - 1} \right)$$

Properties of Matter

The velocity of a small ball of mass 'm' and density d 1 , when dropped in a container filled with glycerin, becomes constant after some time. If the density of glycerin is d 2 , then the viscous force acting on the ball, will be :

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