# Dynamics Problem - Backspin (Friction, Velocity)

A 1.2ft diameter ball is thrown onto a rough surface, such that it has a velocity of 6ft/s and a backspin angular velocity of w. If it is to stop backspinning at the same instant as the velocity is 0, the backspin w in rad/s is what? HINT: The answer is independent of the mass and coefficient of friction.

a. 17.8

b. 22.0

c. 25.0

d. 28.1

*Please see attachment for diagram and figures; please show your work.

© BrainMass Inc. brainmass.com October 9, 2019, 4:33 pm ad1c9bdddfhttps://brainmass.com/engineering/mechanical-engineering/dynamics-problem-backspin-friction-velocity-35548

#### Solution Preview

Let us assume the friction force will be f, acting backward, therefore, the force f will help to reduce the back spinning wo to 0, and and also reduce the forward linear speed ...

#### Solution Summary

The solution is given step-by-step equationally.

$2.19