- #1

AzimD

- 41

- 8

- Homework Statement
- A coin of mass m is on a rigid disk at a distance d from the center of the disk. There is

friction between the coin and the disk. The coefficient of static friction is µs. At time

t = 0, the disk begins to rotate with a constant angular acceleration of magnitude α.

The magnitude of the acceleration due to gravity is g.

Express your answers in terms of some or all of the given variables m, d, µs, α, t, and g

as needed.

(a) While the coin remains at rest relative to the disk, what is fs, the magnitude of

the force of static friction exerted by the disk on the coin as a function of time t?

(b) At what angular speed ω will the coin start to slip with respect to the disk?

- Relevant Equations
- F_c=md(ω^2)

I believe I've solved this problem, however, I got through it pretty quickly and since it's the last problem on the assignment, I feel that I may have had an oversight.

For part a, I got: fs=md(α^2)(t^2)

and for part b, I got: ω=Sqrt((µs*g)/d)

Could someone confirm my answers? I've attached a picture of the problem and my work!

For part a, I got: fs=md(α^2)(t^2)

and for part b, I got: ω=Sqrt((µs*g)/d)

Could someone confirm my answers? I've attached a picture of the problem and my work!