Question

An object of mass $5\text{kg}$ is attached to the hook of a spring balance and the balance is suspended vertically from the roof of a lift. The reading on the spring balance when the lift is going up with an acceleration of $0.25{\text{m/s}}^2$ is $(g=10{\text{m/s}}^2)$

• A. $51.25\text{N}$
• B. $48.75\text{N}$
• C. $52.75\text{N}$
• D. $47.25\text{N}$

Answer 1

The correct option is A $51.25\text{N}$

By FBD,

On moving upward,

Weight, $W=m(g+a)=5(10+0.25)$ $(\because a=0.25{\text{m/s}}^2)$
$W=5\times 10.25=51.25\text{N}$
Hence, the correct answer is option (a).