Rotational Dynamics
What is Newton's Second Law for Rotating Objects?

 
 
 

Compare the terms and units for both this and the original (i.e., translational and rotational) versions of Newton's 2nd law.
 
 
 
 

A potter's wheel has a radius of 0.50 m and a mass of 100.0 kg and is freely rotating at 50.0 rev/min.  The potter can stop the wheel in 6.0 s by pressing a wet rag against the rim.

-a) What is the angular acceleration of the wheel?
 
 
 
 

-b) How much torque does the potter apply to the wheel?
 
 
 
 

What is angular momentum?
 
 
 

What is the formula for angular momentum?
 
 

Compare the terms and units for both this and the original (i.e., translational and rotational) versions of the formula for angular momentum.
 
 
 
 

A 2.0 kg bicycle wheel with a radius of 0.30 m turns at a constant angular speed of 25 rad/s when a 0.30 kg reflector is at a distance of 0.19 m from the axle.  What is the angular speed of the wheel when the reflector slides to a distance of 0.25 m from the axle?
 
 
 

What is rotational kinetic energy?
 
 

What is the basic formula for kinetic energy?
 
 

What is the formula for rotational kinetic energy?
 
 

Write the updated version of the formulas for the conservation of mechanical energy.
 
 

A 1.5 kg bicycle tire with a radius of 0.33 m starts from rest and rolls down from the top of a 14.8 m high hill.  What is the translational speed of the tire when it reaches the bottom of the hill?  (Assume the tire is a hoop with a I = mr2.)
 
 


Copyright Alexplorer. Some items taken from or adapted from other materials. This page is free for use in a classroom setting.
Back to the Physics index