Question1
A 50-kg student on a sled starts from rest at a vertical height of 20 m above horizontal base of a hill and slides down.
a) If sled and the student have a speed of 10 m/s at the bottom of the hill, this system is
(1) conservative, (2) non-conservative, or (3) none of the preceding. Why give reasons?
b) What is work done by the non-conservative force?
Question2
Conceptual provides useful background for this problem. A playground carousel is free to rotate about its center on frictionless bearings, and air resistance is negligible. The carousel itself (without riders) has a moment of inertia of 125 kg·m2. While one person is standing on the carousel at a distance of 1.50 m from center, the carousel has the angular velocity of 0.600 rad/s. yet, as this person moves inward to a point located 0.938 m from the center, the angular velocity increases to 0.800 rad/s. What is person’s mass?