Question

A bullet of mass $m$ strikes an obstruction and deviates off at ${60}^{\circ }$ to its original direction. If its speed is also changed from $u$ to $v$. Find the magnitude of the impulse acting on the bullet?

Answer 1

$changeinmomentum=m(vcos{60}^0-u)\hat{i}+mvsin{60}^0\hat{j}=m(\frac{v}{2}-u)\hat{i}+mv\frac{\sqrt{3}}{2}\hat{j}I=m\sqrt{{(\frac{v}{2}-u)}^2+{\left(v\frac{\sqrt{3}}{2}\right)}^2}=m\sqrt{v^2-uv+u^2}$