A child on a sledge is being pulled along a horizontal path by its parent. The child and sledge have a combined mass of 18 kg and there is a normal contact force of 135 N. Given there
is no resistance to motion and the parent pulls with a force of F N at an angle 25◦
to the
horizontal, then what is F?

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.