The 64.4-lb crate slides down the curved path in the vertical plane. If the crate has a...

The 64.4-lb crate slides down the curved path in the vertical plane. If the crate has a velocity of 3 ft/sec down the incline at A and a velocity of 25 ft/sec at B, compute the work U_ƒ done on the crate by friction during the motion from A to B.