An object is projected upwards with a velocity of $100 \, m/s$. It will strike the ground after (approximately) ........ $sec$.

$A$ man is standing on top of a building $100\, m$ high. He throws two balls vertically,one at $t = 0$ and the other after a time interval $\Delta t$ (less than $2\, s$). The second ball is thrown at a velocity half that of the first. The vertical gap between the first and second ball is $15\, m$ at $t = 2\, s$. The gap is found to remain constant. Calculate the velocity with which the balls were thrown and the exact time interval between their throws.

Two bodies of masses $m_1$ and $m_2$ are dropped from two different heights $h_1$ and $h_2$ respectively. The ratio of the times taken by the two masses to touch the ground is (neglect air resistance)

$A$ body is dropped from a tower of height $h$. It reaches the ground at $t = 4\, s$. What is the height of the tower in $m$?

Which of the following represents the velocity-time graph for a ball thrown vertically upwards (neglecting air resistance)?

What is free fall? Write the equations of uniformly accelerated motion for an object falling freely.