Two blocks of mass $2 \,kg$ and $4 kg$ are accelerated with same acceleration by a force $10 \,N$ as shown in figure on a smooth horizontal surface. Then the spring force between the two blocks will be .......... $N$ (spring is massless)

Calculate $T_1$ and $T_2$

Give the magnitude and direction of the net force acting on a stone of mass $0.1\; kg$,

$(a)$ just after it is dropped from the window of a stationary train,

$(b)$ just after it is dropped from the window of a train running at a constant velocity of $36 \;km/h$,

$(c)$ just after it is dropped from the window of a train accelerating with $1\; m s^{-2}$,

$(d)$ lying on the floor of a train which is accelerating with $1\; m s^{-2}$, the stone being at rest relative to the train.

Neglect air resistance throughout.

A car is moving on an overbridge of radius $R$ with a constant speed $v$. As the car is descending on the overbridge from point $B$ to $C,$ the normal reaction on it due to bridge

Figure shows two cases. In first case a spring (spring constant $K$ ) is pulled by two equal and opposite forces $F$ at both ends and in second case is pulled by a force $F$ at one end. Extensions $(x)$ in the springs will be

A parachutist with total weight $75 \,kg$ drops vertically onto a sandy ground with a speed of $2 \,ms ^{-1}$ and comes to halt over a distance of $0.25 \,m$. The average force from the ground on her is close to ............ $N$