Time of Flight with Incline as Frame of Reference

Q. A truck is moving horizontally with velocity V. A ball is thrown vertically upward with velocity U at an angle$\theta$ to the horizontal from the truck relative to it. The horizontal range of the shell relative to the ground is

1. 
2. 
3. 
4. 

Q. A particle is projected from the bottom of an inclined plane of angle ${30}^{\circ }$ with a velocity of $30\text{m/s}$ at an angle of ${60}^{\circ }$ with the horizontal. Find the time of flight.
(Take $g=10m/s^2$)

1. $\sqrt{3}\text{s}$
2. $\frac{1}{\sqrt{3}}\text{s}$
3. $2\sqrt{3}\text{s}$
4. $2\text{s}$

Q. A particle is projected from the bottom of an inclined plane of angle ${30}^{\circ }$ with a velocity of $30\text{m/s}$ at an angle of ${60}^{\circ }$ with the horizontal. Find the time of flight.
(Take $g=10m/s^2$)

1. $\sqrt{3}\text{s}$
2. $\frac{1}{\sqrt{3}}\text{s}$
3. $2\sqrt{3}\text{s}$
4. $2\text{s}$

Q. A particle is projected with a certain velocity at an angle $\alpha$ above the horizontal from the foot of an inclined plane of inclination ${30}^{\circ }$. If the particle strikes the plane normally. then $\alpha$ is equal to

1. ${30}^{\circ }+{\tan }^{-1}\left(\frac{1}{2\sqrt{3}}\right)$
2. ${45}^{\circ }$
3. ${60}^{\circ }$
4. ${30}^{\circ }+{\tan }^{-1}\left(\frac{\sqrt{3}}{2}\right)$