Two particles having masses $4\, g$ and $16\, g$ respectively are moving with equal kinetic energies. The ratio of the magnitudes of their linear momentum is $n : 2 .$ The value of $n$ will be ...... .

A car accelerates from rest to $u\,m / s$. The energy spent in this process is $E\,J$. The energy required to accelerate the car from $u\,m / s$ to $2u\,m / s$ is $nE\,J$. The value of $n$ is ..............

A spring of unstretched length $l$ has a mass $m$ with one end fixed to a rigid support .Assuming spring to be made of a uniform wire, the kinetic energy possessed by it if its free end is pulled with uniform velocity $v$ is

A body of mass $5\; kg$ is moving with a momentum of $10\; kg m / s$. A force of $0.2\; N$ acts on it in the direction of motion of the body for $10\; sec$. Find the increase in its kinetic energy.

A car travelling at a speed of $30\, km/hour$  is brought to a halt in $8\, m$ by applying brakes. If the same car is travelling at $60 \,km/hour$, it can be brought to a halt with the same braking force in ............... $\mathrm{m}$

The kinetic energy of a body decreases by $36\%$. The decrease in its momentum is ............... $\%$