If the horizontal range of a body projected with a velocity ' $u$ ' is 3 times the maximum height reached by it, then the range of the body is

( $g=$ Acceleration due to gravity)

If the velocity at the maximum height of a projectile projected at an angle of $45^{\circ}$ is $20 \mathrm{~ms}^{-1}$, then the maximum height reached by the projectile is (Acceleration due to gravity $=10 \mathrm{~ms}^{-2}$ )

A body of mass ' $m$ ' moving along a straight line collides with a stationary body of mass ' $2 m^{\prime}$. After collision if the two bodies move together with the same velocity, then the fraction of kinetic energy lost in the process is

If a body of mass 2 kg moving with initial velocity of $4 \mathrm{~ms}^{-1}$ is subjected to a force of 3 N for a time of 2 s normal to the direction of its initial velocity, then the resultant velocity of the body is