Question

Two particles are simultaneously projected in opposite directions horizontally from a given point in space, where gravity g is uniform. If $u_{1} and u_{2}$ and be their initial speeds, then the time t after which their velocities are mutually perpendicular is given by

Moderate

Solution

Given, $v_{1} ⊥ v_{2}$
$∴ v_{1} \cdot v_{2} = 0$
$or (u_{1} \hat{i} - g t \hat{j}) \cdot (- u_{2} \hat{i} - g t \hat{j}) = 0$
$∴ g^{2} t^{2} = u_{1} u_{2} or t = \frac{\sqrt{u_{1} u_{2}}}{g}$

Get Instant Solutions

When in doubt download our app. Now available Google Play Store- Doubts App

Recieve an sms with download link

SCAN ME