Question

A particle A is projected with an initial velocity of $60$ m/s at an angle ${30}^o$ to the horizontal. At the same time a second particle B is projected in opposite direction with initial speed of $50$ m/s from a point at a distance of $100$m from A. If the particles collide in air, find the angle or projection $\alpha$ of particle B.

Answer 1

$uAx=60cos{30}^o=30\sqrt{3}m/s$

$uAy=60sin{30}^o=30m/s$

$uBx=-50cos\alpha$\\ $uBy=50sin\alpha$

A and B reach the same height at same time condition for collision

$uAy=uBy$

$30=50sin\alpha$

$\alpha ={sin}^{-1}\frac{3}{5}$