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 $N$)

$A$ block of mass $M$ is lying on a horizontal frictionless surface. One end of a uniform rope of mass $M/2$ is fixed to the block, which is pulled in the horizontal direction by applying a force $F$ at the other end. The tension in the middle of the rope will be

Two spheres $P$ and $Q$,each of mass $200 \text{ g}$,are attached to a string of length $1 \text{ m}$ as shown in the figure. The string and the spheres are then whirled in a horizontal circle about $O$ at a constant angular speed. The ratio of the tension in the string between $P$ and $Q$ to that between $P$ and $O$ is (where $P$ is at the mid-point of the line joining $O$ and $Q$).

$A$ block of mass $M$ on a horizontal smooth surface is pulled by a load of mass $M/2$ by means of a rope $AB$ and string $BC$ as shown in the figure. The length and mass of the rope $AB$ are $L$ and $M/2$ respectively. As the block is pulled from $AB = L$ to $AB = 0$,its acceleration changes from:

$A$ uniform thick string of length $5\,m$ is resting on a horizontal frictionless surface. It is pulled by a horizontal force of $5\,N$ from one end. The tension in the string at $1\,m$ from the force applied 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 ........ $N$.