Question

Problem 4 [25 pts]. (It is the same physical system as in the Problem 3) A hoop of mass M=400.g and radius R=20.0 cm is rolling without slipping in clockwise direction down an incline plane with the incline angle ? = 20? .

1. How much work is done by frictional force acting on the hoop on (1) translation, (2) rotation of the hoop? Show all work so that your final answer is justified.

2. How much is ???ℎ?? on the hoop? Explain by using your answer from part 1, and whatever other argument you find necessary.

3. If the incline is 40.0 cm long and the hoop started at its top from rest, what angular speed will it have at the bottom? You must use energy methods to obtain your answer!

** Problem 3** Problem 3 [25 pts]. A hoop of mass M=400.g and radius R=20.0 cm is rolling without slipping in clockwise direction down an incline plane with the incline angle ? = 20? . What is the forward acceleration of the hoop (i.e., of its CM), and the frictional force acting on the hoop? FBD is a must! Work out in detail the dynamics equations for translation and rotation of the hoop!

acceleration = 1.68 m/s

friction = 0.67 N

Answer 1