# Solve the following :

Question:

The elevator shown in figure is descending with an acceleration of $2 \mathrm{~m} / \mathrm{s}^{2}$. The mass of the block $A$ is $0.5 \mathrm{~kg}$. What force is exerted by the block $A$ on the block B?

Solution:

$\mathrm{R}=\mathrm{m}_{\mathrm{A}} \mathrm{a}_{0}-0.5 \mathrm{~g}$

$=0.5(2-10)=-4 \mathrm{~N}$

(-ve sign $=>$ force acts opposite to our convention)