The position of a projectile launched from the origin at $t = 0$ is given by $\vec r = \left( {40\hat i + 50\hat j} \right)\,m$ at $t = 2\,s$. If the projectile was launched at an angle $\theta$ from the horizontal, then $\theta$ is (take $g = 10\, ms^{-2}$)
${\tan ^{ - 1}}\frac{2}{3}$
${\tan ^{ - 1}}\frac{3}{2}$
${\tan ^{ - 1}}\frac{7}{4}$
${\tan ^{ - 1}}\frac{4}{5}$
A projectile crosses two walls of equal height $H$ symmetrically as shown If the horizontal distance between the two walls is $d = 120\,\, m$, then the range of the projectile is ........ $m$
A particle is thrown with a speed $u$ at an angle $\theta$ with the horizontal. When the particle makes an angle $\phi$ with the horizontal, its speed changes to $v$, where
Two stones are projected so as to reach the same distance from the point of projection on a horizontal surface. The maximum height reached by one exceeds the other by an amount equal to half the sum of the height attained by them. Then, angle of projection of the stone which attains smaller height is $........$
A ball is projected with kinetic energy $E$ at an angle of ${45^o}$ to the horizontal. At the highest point during its flight, its kinetic energy will be
The angle of projection for a projectile to have same horizontal range and maximum height is :