A block of mass $M$ is pulled along a horizontal frictionless surface by a rope of mass $m$. If a force $P$ is applied at the free end of the rope, the force exerted by the rope on the block is-

- A
$\frac{{Pm}}{{M + m}}$

- B
$\frac{{Pm}}{{M - m}}$

- C
$P$

- D
$\frac{{PM}}{{M + m}}$

The acceleration of $10\,kg$ block when $F =30\,N$

A particle of small mass $m$ is joined to a very heavy body by a light string passing over a light pulley. Both bodies are free to move. The total downward force in the pulley is

A lift is going up. The total mass of the lift and the passenger is $1500\, kg$. The variation in the speed of the lift is as given in the graph. The tension in the rope pulling the lift at $t = 11^{th}\, sec$ will be ............ $N$

In the figure the tension in the diagonal string is $60\,N$.

Find the magnitude of the horizontal force $\overline{ F }_1$ and $\overline{ F }_2$ that must be applied to hold the system in the position shown.

A particle of mass $50$ gram moves on a straight line. The variation of speed with time is shown in figure. find the force acting on the particle at $t =2,4$ and $6$ seconds.