18:10
University Physics with Modern Physics
A small rock with mass 0.20 kg is released from rest at point A, which is at the top edge of a large, hemispherical bowl with radius $R =$ 0.50 m ($\textbf{Fig. E7.9}$). 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. The work done by friction on the rock when it moves from point $A$ to point $B$ at the bottom of the bowl has magnitude 0.22 J. (a) Between points $A$ and $B$, how much work is done on the rock by (i) the normal force and (ii) gravity? (b) What is the speed of the rock as it reaches point $B$? (c) Of the three forces acting on the rock as it slides down the bowl, which (if any) are constant and which are not? Explain. (d) Just as the rock reaches point $B$, what is the normal force on it due to the bottom of the bowl?
Figure E7.9 (Figure can't copy)