Physics - Fluid Question with Solution | TestHub

When the ball has moved through a distance 'vt'. it can be considered to have changed places with a 'honey ball' of identical volume

The momentum of the honey displaced by the ball is required. The volume of honey displaced is equal to the volume of the steel ball, $V=1{\mathrm{cm}}^3$. The density of honey is $\rho =2{\mathrm{gcm}}^{-3}$.

Mass of honey displaced:

$m=\rho V=(2{\mathrm{gcm}}^{-3})(1{\mathrm{cm}}^3)=2\mathrm{g}$

The ball's speed is $v=1{\mathrm{cms}}^{-1}$. The momentum of the displaced honey is:

$P=mv=(2\mathrm{g})(1{\mathrm{cms}}^{-1})=2\mathrm{g}\mathrm{cm}{\mathrm{s}}^{-1}$