$A$ boy playing on the roof of a $10 \, m$ high building throws a ball with a speed of $10 \, m/s$ at an angle $30^{\circ}$ with the horizontal. How far from the throwing point will the ball be at the height of $10 \, m$ from the ground (in $, m$)? $(g = 10 \, m/s^2, \sin 30^{\circ} = 1/2, \cos 30^{\circ} = \sqrt{3}/2)$

$A$ ball is projected upwards from the top of a tower with a velocity of $50 \, ms^{-1}$ making an angle of $30^{\circ}$ with the horizontal. The height of the tower is $70 \, m$. After how many seconds from the instant of throwing will the ball reach the ground?

$A$ bomber plane moves horizontally with a speed of $500\,m/s$ and a bomb released from it,strikes the ground in $10\,s$. The angle with the horizontal at which it strikes the ground will be $(g = 10\,m/s^2)$.

Two objects are located at a height of $10 \ m$ above the ground. At some point in time, the objects are thrown with an initial velocity of $2 \sqrt{2} \ m \ s^{-1}$ at an angle of $45^{\circ}$ and $135^{\circ}$ with the positive $X$-axis, respectively. Assuming $g = 10 \ m \ s^{-2}$, the velocity vectors will be perpendicular to each other at a time equal to: (in $s$)

$A$ bomber plane moves horizontally with a speed of $500 \ m/s$ and a bomb released from it strikes the ground in $10 \ s$. The angle with the horizontal at which it strikes the ground will be $(g = 10 \ m/s^2)$.

An aeroplane is moving with a velocity $u$. It drops a packet from a height $h$. The time $t$ taken by the packet in reaching the ground will be