Two bodies of masses $1 kg$ and $5 kg$ are dropped gently from the top of a tower. At a point $20 cm$ from the ground,both the bodies will have the same

$A$ ball is thrown upward with speed $10 \, m/s$ from the top of a tower and reaches the ground with a speed $20 \, m/s$. The height of the tower is ......... $m$. (Take $g = 10 \, m/s^2$)

Draw the graph of $y$ versus $t$ for an object falling freely,where $y$ is the vertical displacement and $t$ is time.

$A$ body is projected vertically upwards. The times corresponding to a specific height while ascending and while descending are $t_{1}$ and $t_{2}$ respectively. Then the velocity of projection is (where $g$ is acceleration due to gravity).

From a balloon moving upwards with a velocity of $12\,ms^{-1}$,a packet is released when it is at a height of $65\,m$ from the ground. The time taken by it to reach the ground is...........$s$ $(g = 10\,ms^{-2})$.

$A$ ball is thrown upwards. It takes $4 \, s$ to reach back to the ground. Its initial velocity is........$m/s$.