- #1

Krushnaraj Pandya

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## Homework Statement

A solid circular disk (m,R) translates with v1 and rotates with angular velocity w1=2v1/R, at t=0. Because of friction, pure rolling starts at time t. the coefficient of friction is C. Find velocity of center of disk at time t

## Homework Equations

1) for pure rolling v=Rw

2) for translational motion v=u+at

3) for rotational motion w=w1+(alpha)t where alpha is angular acceleration

4) kinetic friction= Cmg

5) Torque=Moment of inertia*alpha

6) Moment of Inertia of disk=(MR^2)/2

## The Attempt at a Solution

using the above equations, V(f)=v1-Cgt and W(f)=V(f)/R={(2v1)/R}-(alpha)t, I found t to be v1/3Cg.

Again, using 2); v at time t=v1-Cgt, putting t I get the answer as 2v1/3 but my textbook says the answer is 4v1/3. Am I making a mistake somewhere?