Intro to Relative Projectile

Q.

Two projectiles are thrown simultaneously in the same plane from the same point. If their velocities are $v_1$ and $v_2$ at angles ${\theta }_1$ and ${\theta }_2$ respectively from the horizontal, then answer the following questions: If $v_{1}cos{\theta }_1$ = $v_{2}cos{\theta }_2$, then choose the incorrect statement

1. one particle will remain exactly below or above the other particle

2. the trajectory of one with respect to other will be vertical straight line

3. both will have the same range

4. none of these

Q.

Two projectiles are thrown simultaneously in the same plane from the same point. If their velocities are $v_1$ and $v_2$ at angles ${\theta }_1$ and ${\theta }_2$ respectively from the horizontal, then answer the following questions: If $v_1$ = $v_2$ and ${\theta }_1>\theta$, then choose the incorrect statement

1. Particle 2 moves under the particle 1

2. The slope of the trajectory of particle 2 with respect to 1 is always positive

3. Both the particles will have the same range if and and =

4. none of these

Q. Two particles are projected simultaneously in the same vertical plane, from the same point, but with different speeds and at different angles to the horizontal. The path followed by one, as seen by the other, till both are in air is

1. A vertical straight line
2. A straight line making a constant angle $(\ne {90}^{\circ })$ with the horizontal
3. A parabola
4. A hyperbola

Q.

A particle is projected vertically upwards from $O$ with velocity $v$ and a second particle is projected at the same instant from $P$ (at a height h above $O$) with velocity $v$ at an angle of projection $\theta$. The time when the distance between them is minimum is

1. $\frac{h}{2vsin\theta }$

2. $\frac{h}{2vcos\theta }$

3. $\frac{h}{v}$

4. $\frac{h}{2v}$