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Angular Momentum -Bike Tire (Katie Flanagan)

CAPE CANAVERAL AIR FORCE STATION, Fla. -- A Delta IV rocket lifts off from here Aug. 29.  A Defense Satellite Communication System was placed into orbit by the rocket.  It was the last of the system to be launched.  (U.S. Air Force photo by Carleton Bailie)

Katie Flanagan

Principle(s) Illustrated

  1. Conservation of Angular Momentum-  Same principle of inertia in linear motion, but it is in rotational motion.  A tire that is spinning wants to keep spinning, and a tire that is still wants to stay still, unless an outside force acts upon it.  
  2. Newton's 3rd Law-- For every action there is an equal and opposite reaction.


  • Science Standard- High School Physics 2.a-h

Questioning Script

Prior knowledge & experience:

Students should know about Newton's laws of motion and they should know the differences between linear and angular momentum. 

Root question:

If I am standing on a spinning plate and holding a bike wheel in the center of its axis, how can I move my body in a complete circle one direction or the other? 

Target response:

Spin the bike tire in your hands, using it like a steering wheel, apply a torgue one direction or the other.  Whichever way you turn the bike tire you will turn the opposite direction on the spinning plate.

Common Misconceptions:

Common misconceptions are that you will spin in whichever direction you turn the wheel, kinda like a steering wheel.  Also, people think that they are able to turn themselves around in a circle without an outside force acting against them, when if fact it is impossible.

Methods and Materials

                    Materials:  1 spinning plate (the less friction the better)-- Can also use a chair
                                      A bicycle tire with a peg in the center

                    Methods:   Start by having a student stand on the spinning plate and try to turn around in a circle. 
                                      They will find that they can not get very far without an outside force.
                                      Then, have them hold the tire by the pegs and spin the tire very fast.  When the student
                                      turns the wheel to the side they will turn around in a circle on the spinning plate.

Photographs and Movies




Reference 1 (give the title of the page and insert a link.  Don't just paste URL)

Reference 1 (give the title of the page and insert a link.  Don't just paste URL)

Real Life Application:  Gyroscope in a rocket ship-- This is how the rocket ship steers.

Gyroscope in a V2 rocket

A similar concept in a different application is when you see figure skaters spinning very quickly on the ice.  When their arms are outstretched they slow down, but when they are tucked in, they speed up.  This is because of the principle of the conservation of angular momentum.