What Is the Angular Acceleration and Distance Traveled by the Paint Splotch?

AI Thread Summary
The problem involves a flywheel that accelerates from 20 rpm to 70 rpm over 30 seconds, with a paint splotch located 0.10 m from the center. To find the angular acceleration, the change in angular velocity must be calculated in rad/s, using the conversion from revolutions per minute to radians per second. The angular acceleration can then be determined by dividing the change in angular velocity by the time interval. Additionally, the distance traveled by the paint splotch can be calculated using the angular displacement during the acceleration period. Understanding these calculations is crucial for solving the problem effectively.
RedDanger
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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! :[
 
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RedDanger said:

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?
 
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(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
 
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