Two carts of masses $200 \, kg$ and $300 \, kg$ on horizontal rails are pushed apart. Suppose the coefficient of friction between the carts and the rails is the same. If the $200 \, kg$ cart travels a distance of $36 \, m$ and stops,then the distance travelled by the cart weighing $300 \, kg$ is ........ $m$.

$A$ force of $5\,N$ acts on a body of mass $5\,kg$ for $1\,s$ and gives it a momentum $p$ and kinetic energy $E$. If the same force accelerates the same body through $1\,m$,the momentum and energy attained by the body are $p'$ and $E'$ respectively. Which of the following relations is correct?

Fill in the blanks:
$(a)$ If a force of $10\, N$ is applied to an object and it produces an acceleration of $1\, m s^{-2}$,then the mass of the object is ...
$(b)$ According to Newton's first law of motion,no force is required to keep an object moving with ......... velocity.
$(c)$ The apparent weight of an object in a lift accelerating upwards is ......... .

Two blocks of equal masses are connected with a massless spring of spring constant $k = 2500 \,N/m$ and natural length $10 \,cm$,resting on a frictionless horizontal plane. If a constant horizontal force $F = 10 \,N$ is applied as shown in the figure,find the maximum distance between the blocks. (in $cm$)

Block $B$ of mass $100 \ kg$ rests on a rough surface with a friction coefficient $\mu = 1/3$. $A$ rope is tied to block $B$ as shown in the figure. The maximum acceleration with which boy $A$ of mass $25 \ kg$ can climb the rope without making the block move is:

$A$ small ball $B$ of mass $m$ is suspended with a light inelastic string of length $L$ from a block $A$ of the same mass $m$,which can move on a smooth horizontal surface as shown in the figure. The ball is displaced by an angle $\theta$ from the equilibrium position and then released. The tension in the string when it is vertical is: