Water is flowing from a horizontal pipe fixed at a height of $2\,m$ from the ground. If it falls at a horizontal distance of $3\,m$ as shown in the figure,the speed of water when it leaves the pipe is $............\,ms^{-1}$ (take $g=9.8\,ms^{-2}$).

Two balls are thrown horizontally from the top of a tower with velocities $v_1$ and $v_2$ in opposite directions at the same time. After how much time will the angle between the velocities of the balls become $90^o$?

$A$ ball of mass $m=1 \, kg$ is thrown from the top of a building with initial velocity $v=(20 \, m/s) \hat{i} + (24 \, m/s) \hat{j}$ at time $t=0$. The change in the potential energy of the ball between $t=0$ and $t=6 \, s$, if the ball does not hit the ground, is (assume $g=10 \, m/s^2$): (in $ \, J$)

An aeroplane moving horizontally with a speed of $720 \, km/h$ drops a food packet while flying at a height of $396.9 \, m$. The time taken by the food packet to reach the ground and its horizontal range are (Take $g = 9.8 \, m/s^2$):

From the top of a tower of height $40 \ m,$ a ball is projected upwards with a speed of $20 \ m/s$ at an angle $30^{\circ}$ to the horizontal. The ball will hit the ground in time ........ $s$ (Take $g = 10 \ m/s^2$)

$A$ ball is thrown upward from the top of a building at an angle of $30^{\circ}$ to the horizontal and with an initial speed of $20 \,m/s$. If the ball strikes the ground after $3 \,s$, then the height of the building is (acceleration due to gravity $g = 10 \,m/s^2$) (in $\,m$)