A boy throws a ball with a velocity $u$ at an angle $\theta$ with the horizontal. At the same instant he starts running with uniform velocity to catch the ball before if hits the ground. To achieve this he should run with a velocity of
$u \cos \theta$
$u \sin \theta$
$u \tan \theta$
$u \sec \theta$
A ball of mass $160\, g$ is thrown up at an angle of $60^{\circ}$ to the horizontal at a speed of $10 \,m / s$. The angular momentum of the ball at the highest point of the trajectory with respect to the point from which the ball is thrown is nearly $\left(g=10\, m / s ^{2}\right)$ (in $kgm ^{2} / s$)
A cricketer can throw a ball to a maximum horizontal distance of $100\; m$. How much high above (in $m$) the ground can the cricketer throw the same ball ?
The position coordinates of a projectile projected from ground on a certain planet (with no atmosphere) are given by $y=\left(4 t-2 t^2\right) m$ and $x =(3 t)$ metre, where $t$ is in second and point of projection is taken as origin. The angle of projection of projectile with vertical is .........
A particle $A$ is projected vertically upwards. Another identical particle $B$ is projected at an angle of $45^o $ . Both reach the same height. The ratio of the initial kinetic energy of $A$ to that of $B$ is