Calculating Angular Acceleration and Distance Traveled of Paint Splotch on Flywheel

[RedDanger]

Homework Statement

A flywheel rotates at a rate of 20 rpm. A motor provides a constant angular
acceleration so that 30 s later it turns at a rate of 70 rpm. There’s a tiny splotch of paint on the
flywheel, located 0.10 m from its center. During the acceleration period, what is the angular
acceleration of the splotch of paint in rad/s2, and how far does the splotch of paint travel?

Homework Equations

C = 2pi*r ?

The Attempt at a Solution

I have no idea how to approach this problem, as I missed this day in class and my text isn't very helpful. Even worse, my professor doesn't have any office hours this week! :[

 

[rock.freak667]

The Attempt at a Solution

I have no idea how to approach this problem, as I missed this day in class and my text isn't very helpful. Even worse, my professor doesn't have any office hours this week! :[

Firstly, read http://hyperphysics.phy-astr.gsu.edu/hbase/rotq.html" for the equations (scroll down to Description of equations)

It asks you to get the angular acceleration, so which equation will give you that value given just the angular velocity (which you can get the change in) and time?

 

[pfunk22]

(revolutions per minute) x ( (2*pi) / (60sec) )= omega in rad/sec

you want to find the change in omega over time, or alpha in rad/sec^2