Question

The elevator shown in the figure is descending with an acceleration of $2{\text{ms}}^{-2}$. The mass of the block $A=0.5\text{kg}$. The force exerted by the block $A$ on the block $B$ is $(g=10{\text{ms}}^{-2})$

• A. $2\text{N}$
• B. $4\text{N}$
• C. $6\text{N}$
• D. $8\text{N}$

Answer 1

The correct option is B $4\text{N}$

When the elevator moves downward with acceleration ${}^{\prime }{a}^{\prime }$, net normal $\left(N\right)$ force acting by A on B will be,

$N=m_A(g-a)=0.5(10-2)=4\text{N}$