Abody 'a' of mass 1.5kg travelling along the positive x-axis with speed of 4.5m/s collides with another body 'b' of mass 3.2kg, which initially is at rest as a result of the collision, 'a' is deflected and moves in a speed of 2.1m/s in a direction which is at an angle of 30 degree below the x-axis. 'b' is set in motion at an angle φ above the x-axis. calculate the velocity of 'b' after the collision.

One hazard of space travel is debris left by previous missions. there are several thousand masses large enough to detect by radar orbiting the earth, but there are far greater numbers of very small masses such as flakes of paint. calculate the force exerted by a 0.110 mg chip of paint that strikes a space shuttle window at a relative speed of 5.00 ✕ 103 m/s and sticks, given the collision lasts 6.00 ✕ 10-8 s. such a collision chipped the window of the ill-fated challenger in june 1983, causing $50,000 of damage.