Question1
A student who weighs 490 N is wearing a backpack that weighs 88 N. The student is standing still on level ground. Give the answers to the following questions in Newton's.
(a) What is magnitude of the net force on the student?
(b) What is magnitude of the contact force on the student by the backpack?
(c) What is magnitude of the contact force on the student by the ground?
Question2
A small rock with mass 0.20 kg is released from rest at point A, that is at the top edge of a large, hemispherical bowl with radius R = 0.50 m. suppose the size of the rock is small compared to R, and assume the rock slides rather than rolling. The work done by friction on the rock when it moves from point A to point B at the bottom of the bowl is -0.22 J. What is a speed of the rock when it reached point B?