A truck is moving on the horizontal road with constant speed $v.$ A ball is thrown from the truck vertical up at speed $u$ $w.r.t.$ truck. What is distance traversed by the truck when ball returns on the truck
$\frac {uv}{g}$
$\frac {2uv}{g}$
$\frac {3uv}{g}$
$\frac {uv}{2g}$
A cannon on a level plane is aimed at an angle $\theta $ above the horizontal and a shell is fired with a muzzle velocity ${v_0}$ towards a vertical cliff a distance $D$ away. Then the height from the bottom at which the shell strikes the side walls of the cliff is
The horizontal range is four times the maximum height attained by a projectile. The angle of projection is ......... $^o$
Given below are two statements. One is labelled as Assertion $A$ and the other is labelled as Reason $R$.
Assertion A :Two identical balls $A$ and $B$ thrown with same velocity '$u$ ' at two different angles with horizontal attained the same range $R$. If $A$ and $B$ reached the maximum height $h_{1}$ and $h_{2}$ respectively, then $R =4 \sqrt{ h _{1} h _{2}}$
Reason R: Product of said heights.
$h _{1} h _{2}=\left(\frac{u^{2} \sin ^{2} \theta}{2 g }\right) \cdot\left(\frac{u^{2} \cos ^{2} \theta}{2 g }\right)$
Choose the $CORRECT$ answer
Four bodies $P, Q, R$ and $S$ are projected with equal velocities having angles of projection $15^{\circ}, 30^{\circ}, 45^{\circ}$ and $60^{\circ}$ with the horizontals respectively. The body having shortest range is
A projectile fired at $30^{\circ}$ to the ground is observed to be at same height at time $3 s$ and $5 s$ after projection, during its flight. The speed of projection of the projectile is $.........\,ms ^{-1}$(Given $g=10\,m s ^{-2}$ )