Write condition for equilibrium when two force act on a particle.

Three blocks of masses ${m_1},\,{m_2}$ and ${m_3}$ are connected by massless strings as shown on a frictionless table. They are pulled with a force ${T_3} = 40\,N$. If ${m_1} = 10\,kg,\,{m_2} = 6\,kg$ and ${m_3} = 4\,kg$, the tension ${T_2}$ will be ........ $N$

There are four forces acting at a point $P$ produced by strings as shown in figure. Which is at rest ? Find the forces $F_1$ and $F_2$.

Two masses $M$ and $m$ are connected by a weightless string. They are pulled by a force $F$ on a frictionless horizontal surface., the acceleration of mass $m$ is

A parachutist of weight $‘w’$ strikes the ground with his legs fixed and comes to rest with an upward acceleration of magnitude $3 \,g$. Force exerted on him by ground during landing is

Ten one-rupeed coins are put on top of each other on a table. Each coin has mass $m$. The reaction of the $6^{th}$ coin (counted from the bottom) on the $7^{th}$ coins is .......... $mg$