Two blocks of masses $2m$ and $m$ are placed on a smooth horizontal surface. $A$ force $F$ is applied on the $2m$ block towards the right,and the same force $F$ is applied on the $m$ block towards the left. What is the ratio of the contact forces between the two blocks in the two cases?

An elevator accelerates upwards at a constant rate. $A$ uniform string of length $L$ and mass $m$ supports a small block of mass $M$ that hangs from the ceiling of the elevator. The tension at distance $l$ from the ceiling is $T$. The acceleration of the elevator is

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 $N$)

$A$ constant horizontal force $\overrightarrow{F}$ of magnitude $10 \,N$ is applied to a block $A$ and this produces an acceleration of magnitude $20 \,m/s^2$. If this block $A$ is then kept against another block $B$ of mass $1.5 \,kg$ as shown in the figure and a force $F^{\prime}$ of $20 \,N$ is applied,find the force on the block $B$. Neglect friction. (in $N$)

$A$ force $F = 10t$ acts on a block of mass $10 \, kg$ as shown in the figure. Find the time $t$ when the block loses contact with the surface.

$A$ horizontal force of $10 \,N$ is applied to a block $A$ as shown in the figure. The masses of blocks $A$ and $B$ are $2 \,kg$ and $3 \,kg$ respectively. The blocks slide over a frictionless surface. The force exerted by block $A$ on block $B$ is: