The tension in the string connected between blocks is ......... $N$

Two blocks of masses $5\, kg$ and $4\, kg$ are in contact with each other on a frictionless table. When a horizontal force of $9\, N$ is applied to the block of mass $5\, kg$ , then the value of the force of contact between the two blocks is ........ $N$

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 will be

A body of mass $1\, kg$ lies on smooth inclined plane. The body is given force $F = 10N$  horizontally as shown. The magnitude of net normal reaction on the body is 

Three blocks $A, B$ and $C,$ of masses $4\, kg, \,2 \,kg$ and $1\, kg$ respectively, are in contact on a frictionless surface, as shown. If a force of $14\, N$ is applied on the $4 \,kg$ block, then the contact force between $A$ and $B$ is  .......... $N$

Two block of masses $7\, kg$ and $5\, kg$ are placed in contact with each other on a smooth surface. If a force of $6\, N$ is applied on the heavier mass, the force on the lighter mass is ............ $N$