Man $A$ of mass $60 \mathrm{kg}$ pushes the other man $B$ of mass $75 \mathrm{kg}$ due to which man $B$ starts moving with acceleration $3 \mathrm{m} {\mathrm{s}}^{-2}$. Calculate the acceleration of man $A$ at that instant.

Find the acceleration of the $6 \mathrm{kg}$ block in the figure. All the surfaces and pulleys are smooth. Also the strings are inextensible and light. [Take $g=10 \mathrm{m} {\mathrm{s}}^{-2}$]

A painter of mass $M$ stands on a platform of mass $m$ and pulls himself up by two ropes which hang over pulley as shown. He pulls each rope with the force $F$ and moves upward with uniform acceleration $a$. Find $a$.

Three monkeys $A, B$ and $\mathrm{C}$ with masses of $10, 15 \mathrm{and} 8 \mathrm{kg}$ respectively are climbing up and down the rope suspended from $D$. At the instant represented, $A$ is descending the rope with an acceleration of $2 \mathrm{m} {\mathrm{s}}^{-2} \mathrm{and} C$ is pulling itself up with an acceleration of $1.5 \mathrm{m} {\mathrm{s}}^{-2}$. Monkey $B$ is climbing up with a constant speed of $0.8 \mathrm{m} {\mathrm{s}}^{-1}$. Calculate the tension $T$ in the rope at $D. (g=10 \mathrm{m} {\mathrm{s}}^{-2})$

An object of mass $2 \mathrm{kg}$ moving with constant velocity $10\hat{\mathrm{i}} \mathrm{m} {\mathrm{s}}^{-1}$ is seen in a frame moving with constant velocity $10\hat{\mathrm{i}} \mathrm{m} {\mathrm{s}}^{-1}$. What will be the value of ‘pseudo force’ acting on object in this frame.

In the adjoining figure, a wedge is fixed to an elevator moving upwards with an acceleration $a$. A block of mass $m$ is placed over the wedge. Find the acceleration of the block with respect to the wedge. Neglect friction.

Which figure represents the correct $\mathrm{F}.\mathrm{B}.\mathrm{D}.$ of the rod of mass m as shown in the figure:

Two blocks are in contact on a frictionless table. One has mass $m$ and the other $2m$. A force $F$ is applied on $2m$ as shown in the figure. Now the same force $F$ is applied from the right on $m$. In the two cases respectively, the ratio of force of contact between the two blocks will be