Question

Two particles are projected simultaneously in a vertical plane from the same point. These particles have different velocities at different angles with the horizontal. The path seen by each other is

• A. Parabola
• B. Hyperbola
• C. Elliptical
• D. Straight line.

Answer 1

Answer: (D)

Straight line.

Answer 2

Here, $\overrightarrow{v}$₁ = (u₁ cosα₁)$\widehat{i}$ + (u₁ sin α₁ - gt)$\widehat{j}$

and $\overrightarrow{v}$₂ = (u₁ cosα₂)$\widehat{i}$ + (u₁ sin α₂ - gt)$\widehat{j}$

Relative velocity $\overrightarrow{v}$₁₂ = $\overrightarrow{v}$₁ - $\overrightarrow{v}$₂ has horizontal as well as vertical components and it is constant also, so that path seen by each other is straight line with angle not equal to 90⁰.