Question

A food packet is dropped from a plane going at an altitude of 100 m. What is the path of the packet as seen from the plane?

• A. A straight line in the south east direction
• B. A straight line moving in the south west direction
• C. Straight line perpendicular to the horizontal
• D. A parabolic path

Answer 1

Answer: (C)

Straight line perpendicular to the horizontal

Solution:

Let $v_1$ be the velocity of the plane w.r.t to ground.

$\therefore$ $v_A$ = $v_1\hat{i}$

$\therefore$ Then $v_B$ = $v_1\hat{i}-gt\hat{j}$

As the package has an initial velocity of $v_1\hat{i}$ and an acceleration of $g$ downwards now velocity of $B$ w.r.t $A$

$v_{BA}$ = $v_B$ - $v_A$

= $v_1\hat{i}$ - $gt\hat{j}$ - $v_1\hat{i}$

= $-gt\hat{j}$

$\therefore$ The package will look like it is falling vertically downward w.r.t. the plane.