# Physics

posted by
**Tom**
.

HELP! I'm doing a webassign, and am completley lost on these problems. If you could help with any, that would be great.

A crate weighing 9.40 103 N is pulled up a 36° incline by a force parallel to the plane. If the coefficient of kinetic friction between the crate and the surface of the plane is 0.750, what is the magnitude of the applied force required to move the crate at a constant velocity?

A 125 m long ramp is to be built for a ski jump. If a skier starting from rest at the top is to have a speed no faster than 27 m/s at the bottom, what should be the maximum angle of inclination?

While catching a baseball that is traveling horizontally at a speed of 12 m/s, a player's glove and arm move straight backward 25 cm from the time of contact to the time the ball comes to rest. If the ball has a mass of 0.20 kg, what is the average force on the ball during that interval?