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Mechanics Demos

Click on any link in order to view the demonstration with an instructional video. Additionally, there are procedure/activity plans listed for some of the demonstrations below. If you have an idea for an activity plan, download the demonstration template from the navigation panel, fill it out and email it to

Airplane Wing Model
A portion of a airplane wing made out of cardboard and plastic is mounted to a scale. One will below air over the wing with a vacuum to show how the wing can rise and fall.
Long metal track that has air being blown through tiny holes on the track to make a near frictionless surface. Cars sit on the track and can be pushed in one direction to demonstrate collisions.
Same Angle, Different Arcs
Series of pulleys with different radii with string wrapped around. Demonstrates for a given rotation, the arcs of two different size circles are not the same.
Angular Momentum
Demonstrate conservation of angular momentum with heavy spinning metal disk.
CAUTION: Keep hands away from disk when spinning, let slow down either naturally or reverse the device used to speed the disk up.
Archimedes Principle
Small tank with water to demonstrate Archimedes principle.
Atom and Molecule Models
Several rigid molecular models.
Atwood Machine
Single pulley with a string wrapped around it that masses can hang on either side. Demonstrates equilibrium/non-equilibrium of forces.
Ball on a String
Wooden ball attached to a string to be swung in a circle to show circular motion.
Ballistics Car
Car that has a spring loaded ball bearing that, when released, shoots straight up in the air. If the car is in motion, the ball will land back in the tube every time.
Bernoulli Kit
Variety of objects used to demonstrate Bernoulli principles.
Center of Mass Board
Metal bar with holes drilled into it that sticks directly to the chalkboard. Hangers are on each side and one can hang mass on the hangers to demonstrate equilibrium of forces and torques.
Center of Mass Demos
Variety of objects to show the center of mass.
Chaotic Double Pendulum
Double pendulum that can swing through itself. Depending on initial conditions, can also exhibit periodic motion.
Compression Syringe
Piston with cotton in it, when compressed fast enough the cotton catches fire and flashes.
Example Procedure
Conservation of Angular Momentum 1
Student will stand (or sit) on rotating table with hard plastic wheel. Spin the wheel and have the student flip the wheel over and see that he/she starts to rotate on the stool, flip it back over and observe that they stop.
Conservation of Angular Momentum 2
Have student sit on rotating stool and tuck hands and feet in. Spin the student and then have them stick their hands and feet out and observe that their angular velocity slows. Can also be used with students holding 1 Kg masses in each hand and just extend and retract arms. 
Example Procedure
Conservation of Angular Momentum 3
Let the hard plastic wheel dangle. When the wheel is not spinning, it wants to lay flat. When the wheel is spinning, it tries to stand up and will precess.
Example Procedure
Doppler Effect
Bluetooth speaker that will play frequency that is swung around your head to demonstrate the shift in sound when the speaker is approaching you or moving away from you.
Doppler Effect Football
A football implanted with a sound generating device which when thrown demonstrates the Doppler effect.
Earth Moon Model
Several Earth-moon/solar system models.
Steel gyroscope to demonstrate conservation of angular momentum. 
Hoop and Disc on Incline
Place a hoop and a disc of the same radius on an incline and release them at the same time to see which one will reach the bottom first. Demonstrates moments of inertia and conservation of energy.
Example Procedure
Horizontally and Vertically Dropped Balls
Ball dropped and shot horizontally at the same time will hit the ground first.
Example Procedure
Hydraulic Press
Use hydraulic press to show the effects of pressure. Place a board in the press and have a student pump the press and show that the board is easily broken.
Incline Plane
Block is placed on adjustable incline with string attached to it that will lay over a pulley at the end of the incline. Masses can be attached to the string.
Example Procedure
Inertia: Mass on Cardboard Ring
Cardboard ring is placed on top of a flask and mass on top of the ring. User then hits the ring out from under the mass. The actions takes place before the inertia of the mass is overcome and the mass falls directly down into the flask.
Inertia: Breaking String
A heavy ball is suspended from a ring stand by string. Attached to the bottom of the ball is another string. If one pulls fast on the bottom, the bottom string will break every time because the inertia of the heavy ball cannot be overcome in such a small amount of time. If one pulls slowly, the top string breaks.
CAUTION: Heavy object falling-keep feet clear.
Loop the Loop
Ball bearing is placed at top of loop the loop and released and it will go around the loop. If placed on the other side it will not make it around the loop because of the lack of energy. Demonstrates conservation of energy.
Example Procedure
Masses and Colored Springs
Assortment of masses and colored sprig with different spring constants are laid out to demonstrate the dependence of the restoring force on spring constants. Can also be used to show periodic motion.
Example Procedure
Three or more metronomes are placed on a board that is free to roll. Even if placed on the board out of sync, the beat frequency and freely moving board will damp out all other frequencies until all of the metronomes are either in sync or not oscillating at all.
Moment of Inertia Bars
Two bars of identical mass do not twist with the same angular velocity or ease. The reason is that on of the bars has all of the mass located at the center of the bar and the other has the mass equally distributed at the each end causing two different moments of inertia.
Example Procedure
Monkey Hunter
Cannon is aligned such that if there were no gravity or air resistance the ball would travel in a straight line and strike a hanging target. when the ball is fired, the target is released and the ball still strikes the falling target every time. 
Example Procedure
Simple hanging bob to be used as a pendulum.
Penny and the Feather
Tip over the tube with a penny and feather and observe that the feather falls slower. Removed the air and observe they both fall at the same rate.
Example Procedure
Pile Driver
Large block confined to a vertical path. Pull it up and let it drop to drive nails into a block of wood.
Rocket Bike
Modified fire extinguisher attached to bike. When extinguisher expels gas, the bike is pushed forward.   
CAUTION: Contents under pressure should not be directed towards audience.
Rocket Propulsion
CO2 cartridge is placed in this apparatus and when the cartridge is pierced, the the thrust makes the arms spin.
Example Procedure
Simple scale to demonstrate introductory physics concepts.
Slug Gun
The gun is cocked back and action is held in place by string, the user then loads the slug in the front of the gun.  User lights a match and when the string breaks it launches the slug out of the gun. In order to conserve momentum, the gun moves back as it launches the slug.
Example Procedure
Torsion Pendulum
Displace the torsion spring by rotating the apparatus clockwise or counter-clockwise. Release and the apparatus will exhibit periodic motion.
Tuning Forks
Several tuning forks to show constructive and destructive sound wave interference, energy transfer, or doppler effect.
Vector Arrows
Wooden arrows with magnets in them to demonstrate vector properties. Vectors stick directly to chalk board and can be fixed in all three directions (x,y,z).
Water in the Bucket
Water is placed in a bucket and is swung in a circle to show that the water will stay in the bucket even when swung upside down.
Example Procedure
Wind Tunnel
Track how air moves around a variety of stationary or spinning objects. 
NOTE: Need 72 hours notice to guarantee dry supply.