Question

A uniform shell explode into three equal parts. Two of the parts fly off perpendicular to each other with velocity $9m{s}^{-1}$ and $12m{s}^{-1}$. Find the velocity of the third part.

Answer 1

$\left(y=-12\right)$
$\overrightarrow{V}g3rdparticle$
$\overrightarrow{V}=-9i-12j$
Let $V$ vector makes $\theta$ with $X$ axis
$\tan \theta =\frac{y}{x}=\frac{-12}{-9}=\frac{4}{3}$
and it is 3rd Quadrant
$\theta$=$180+53$ anti clockwise
or ${127}^{\circ }$ Clockwise $wrt$ $9m/s^2$