$A$ block of mass $M$ is hanging over a smooth and light pulley through a light string. The other end of the string is pulled by a constant force $F$. The kinetic energy of the block increases by $20\,J$ in $1\,s$.

Two blocks $A$ and $B$ of masses $1.5 \ kg$ and $0.5 \ kg$ respectively are connected by a massless inextensible string passing over a frictionless pulley as shown in the figure. Block $A$ is lifted until block $B$ touches the ground and then block $A$ is released. The initial height of block $A$ is $80 \ cm$ when block $B$ just touches the ground. The maximum height reached by block $B$ from the ground after the block $A$ falls on the ground is (in $cm$)

In the case of a wire having negligible mass,suspended from a ceiling and stretched under the action of a weight $F$ suspended from its other end,the tension at any cross-section of the wire is

$A$ monkey of mass $50\,kg$ climbs on a rope which can withstand the tension $(T)$ of $350\,N$. If the monkey initially climbs down with an acceleration of $4\,m/s^2$ and then climbs up with an acceleration of $5\,m/s^2$,choose the correct option $(g = 10\,m/s^2)$.

$A$ light spring balance hangs from the hook of another light spring balance,and a block of mass $M \, kg$ hangs from the lower one. Which of the following statements is true regarding the scale readings?

$A$ mass of $1 \ kg$ is suspended by a string $A$. Another string $C$ is connected to its lower end (see figure). If the string $C$ is stretched slowly,then