$A$ ball is thrown vertically upwards from the top of a tower with a velocity $u$. This ball reaches the ground level with a velocity $4u$. The height of the tower is:

When a ball is thrown up vertically with velocity $V_o$,it reaches a maximum height of $h$. If one wishes to triple the maximum height,then the ball should be thrown with what velocity?

Two balls $A$ and $B$ are thrown with the same velocity $u$ from the top of a tower. Ball $A$ is thrown vertically upwards and ball $B$ is thrown vertically downwards. If $t_A = 6 \ s$ and $t_B = 2 \ s$,then the velocity $u$ of each ball is ....... $m/s$.

What is the distance covered by a freely falling body in the first second (in $m$)? $(g = 10 \ m/s^2)$

$A$ body thrown vertically up with initial velocity $52 \,m/s$ from the ground passes twice a point at $h$ height above at an interval of $10 \,s$. The height $h$ is .........$m$ $(g=10 \,m/s^2)$.

$A$ ball is thrown upward from the ground with an initial speed of $v$. At the same instant, another ball is dropped from a building of height $20 \,m$. If the balls are at the same height after $0.8 \,s$, then the magnitude of $v$ is (Take, acceleration due to gravity $=10 \,ms^{-2}$) (in $\,ms^{-1}$)