The figure shows three blocks in contact and kept on a smooth horizontal surface. What is the ratio of the force exerted by block $A$ on $B$ to that of $B$ on $C$?

$A$ 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 ......... $N$.

$A$ smooth right-angled wedge of mass $M$ is kept on a smooth horizontal surface as shown. $A$ mass $m$ is released from the top of the wedge. When $m$ reaches the ground, its speed is $V$. Find the work done by the normal contact force on $m$ while it comes down to the ground.

$A$ uniform rope of mass $1.0 \ kg$ is connected to a box of mass $2.0 \ kg$,which is placed on a smooth horizontal surface. The free end of the rope is pulled horizontally by a force of $6 \ N$. Find the tension at the midpoint of the rope. ............ $N$

$A$ mass $1\, kg$ is suspended by a thread. It is
$(i)$ lifted up with an acceleration $4.9\, m/s^2$
$(ii)$ lowered with an acceleration $4.9\, m/s^2$.
The ratio of the tensions is

Three masses of $16 \, kg$,$8 \, kg$,and $4 \, kg$ are placed in contact as shown in the figure. If a force of $140 \, N$ is applied on the $4 \, kg$ mass,then the force on the $16 \, kg$ mass will be ............ $N$.