A small rock with mass 0.28 kg is released from rest at point A, which is at the top edge of a large, hemispherical bowl with radius R=0.46 m. Assume that the size of the rock is small compared to R, so that the rock can be treated as a particle, and assume that the rock slides rather than rolls. If the surface of the bowl is frictionless, (a) what is the speed of the rock as it reaches point B? (b) What is the work done by gravity on the rock as it moves from point A to point B?

Aball is thrown from the top of a building with an initial velocity of 21.9 m/s straight upward, at an initial height of 51.6 m above the ground. the ball just misses the edge of the roof on its way down, as shown in the figure. (a) determine the time needed for the ball to reach its maximum height. (b) determine the maximum height. (c) determine the time needed for the ball to return to the height from which it was thrown, and the velocity of the ball at that instant. (d) determine the time needed for the ball to reach the ground. (e) determine the velocity and position of the ball at t = 5.35 s.