A ball is projected from the ground at angle $\theta$with horizontal. After 1s, it is moving at angle ${45}^{\circ }$ with horizontal and after 2s it is moving horizontally. What is velocity of projection of the ball?

Q. A ball is projected from the ground at angle $\theta$ with the horizontal. After $1s$, it is moving at angle ${45}^{\circ }$ with the horizontal and after $2s$ it is moving horizontally. What is the velocity of projection of the ball?

Q. A ball is projected from the ground at angle 0 with the horizontal. After 1 sec it is moving at angle ${45}^{\circ }$ with the horizontal and after 2s it is moving horizontally. What is the velocity of projection of the ball ? (Take $g=10{ms}^{-2}$)

Q. A body is projected with a velocity $v$ at an angle of projection $\theta$ with the horizontal. The direction of velocity of the body makes angle ${30}^{\circ }$ with the horizontal at $t=2\text{s}$ and then after further $1\text{s}$, it reaches the maximum height. Then
$(g=10{\text{m/s}}^2)$

Q. A body is projected with a velocity of $30\text{m/s}$ at an angle of ${60}^{\circ }$ to the horizontal. Find the magnitude of velocity when the angle between the velocity vector and acceleration vector is ${120}^{\circ }$.

Q. A particle is projected at an angle of ${60}^{\circ }$ above the horizontal with a speed of $10m/s$. After some time, the direction of its velocity makes an angle of ${30}^{\circ }$ above the horizontal. The speed of the particle at this instant is