A boy playing on the roof of a $10\, m$ high building throws a ball with a speed of $10\,m/s$ at an angle of $30^o$ with the horizontal. How far from the throwing point will the ball be at the height of $10\, m$ from the ground ? $\left[ {g = 10\,m/{s^2},\sin \,{{30}^o} = \frac{1}{2},\cos \,{{30}^o} = \frac{{\sqrt 3 }}{2}} \right]$
$5\sqrt 5 $
$6$
$3$
$5\sqrt 3 $
A body is projected horizontally from the top of a tower with initial velocity $18\,m s^{-1}$. It hits the ground at angle $45^o$. What is the vertical component of velocity when it strikes the ground ......... $ms^{-1}$
A particle covers $50\, m$ distance when projected with an initial speed. On the same surface it will cover a distance, when projected with double the initial speed ......... $m$
A projectile crosses two walls of equal height $H$ symmetrically as shown The maximum height of the projectile is ........ $m$
A particle is thrown with a velocity of $u \,m / s$. It passes $A$ and $B$ as shown in figure at time $t_1=1 \,s$ and $t_2=3 \,s$. The value of $u$ is ....... $m / s$ $\left(g=10 \,m / s ^2\right)$
A stone is projected with a velocity $20 \sqrt{2}\,m / s$ at an angle of $45^{\circ}$ to the horizontal. The average velocity of stone during its motion from starting point to its maximum height is $..........\,m/s$ (take $g=10\,m / s ^2$ )