If all surfaces are smooth,then the acceleration of mass $m_2$ will be $-$

$A$ dynamometer $D$ is attached to two blocks of masses $6 \, kg$ and $4 \, kg$ as shown in the figure. The reading of the dynamometer is ............ $N$.

Two blocks of masses $6 \ kg$ and $4 \ kg$ are placed in contact with each other on a smooth surface as shown. If a force of $5 \ N$ is applied on the heavier block,the force on the lighter block is (in $N$)

Three identical particles of mass $m$ are joined together by a thread as shown in the figure. All three particles are moving in a horizontal plane in a circle about the point $O$. If the velocity of the outermost particle is $v_0$,then the ratio of tensions in the three sections of the string is:

Two blocks of $7\,kg$ and $5\,kg$ are connected by a heavy rope of mass $4\,kg$. An upward force of $200\,N$ is applied as shown in the diagram. The tension at the top of the heavy rope at point $P$ is ....... $N$ $(g = 10\,m/s^2)$.

$A$ monkey of mass $20 \, kg$ climbs up a rope which can withstand a maximum tension of $25 \, kgf$. What is the maximum acceleration with which the monkey can climb up? (Take $g = 10 \, m/s^2$)