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Mechanics
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Measurement
One-Dimensional Motion
Two-Dimensional Motion
Newton's First Law
Statistics of Rigid Bodies
Applications of Newton's Laws
Work and Energy
Linear Momentum
Rotational Dynamics
Properties of Matter


1A - Measurement

10. Basic Units

1A10.1 Kilogram Mass and Meter Stick

60. Scaling

1A60.1 "Powers of Ten" Video
A ten minute video that begins at the scale of a picnic in Chicago, zooms gradually out to the edge of the visible universe, then zooms back in to the nucleus of a carbon atom.
[Set-Up Time: 10 min.]

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1C - One-Dimensional Motion

10. Velocity

1C10.1 Air Track and Rider
A rider on a frictionless, level air-track moves with constant velocity.
[Set-Up Time: 10 min.]

20. Uniform Acceleration

1C20.1 Coin and Feather Dropped in a Vacuum
In an evacuated tube, a coin and a feather are released simultaneously by an electromagnetic switch. (This demonstration is difficult to repeat, since the cylinder must be opened to set things up again.)
[Set-Up Time: 15 min.]

1C20.2 Inclined Air Track with Blinking Lights
A rider accelerates down an inclined air-track while a series of lights flashes behind it. The spacing of the lights is such that the rider will pass each one just as it flashes, demonstrating the effect of uniform acceleration.
[Set-Up Time: 15 min.]

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1D - Two-Dimensional Motion

40. Motion of the Center of Mass

1D40.1 Tossing an Irregularly-Shaped Disk
An irregularly-shaped disk can be tossed, and the red target painted at its center of mass will be seen to follow a smooth trajectory. See Also: 1J10.1 Center of Gravity of Irregular Shape
[Set-Up Time: 1 min.]

1D40.2 Air Track Inchworm
Two riders are attached by a spring with a card on the spring indicating the center of mass.
[Set-Up Time: 10 min.]

1D40.3 Two-Body System on Air Table
Two pucks of similar or different masses are attached together by string or a rod, and the center of mass can be seen to follow a smooth trajectory.
[Set-Up Time: 20 min.]

50. Central Forces

1D50.1 Ball on String
A lightweight ball can be twirled around in a vertical circle.
[Set-Up Time: none]

1D50.2 Pail of Water
A pail of water can be whirled around a vertical circle and over one's head.
[Set-Up Time: 2 min.]

1D50.3 Conical Pendulum
Rooms 301 and 428 only -- The 50 lbs. ball is suspended from the ceiling and used as a conical pendulum.
[Set-Up Time: 5 min.]

52. Deformation by Central Forces

1D52.1 Centrifuge Hoops
Two hoops become oblate when rotated around an axis along their diameters.
[Set-Up Time: 5 min.]

1D52.2 Candle on a Rotating Platform
A candle is placed under a glass dome on a rotating platform.
[Set-Up Time: unknown]

55. Centrifugal Escape

1D55.1 Grinding Wheel
Show the path of sparks flying off a grinding wheel.
[Set-Up Time: 10 min.]

60. Projectile Motion

1D60.1 Falling Pucks
Two pucks, one at rest and the other in horizontal motion, are released simultaneously from the same height, and strike the table at the same time.
[Set-Up Time: 5 min.]

1D60.2 Shoot the Monkey
A spring-loaded gun is aimed at a monkey suspended by an electromagnet. When the projectile leaves the tip of the gun, the monkey is released and both fall at the same rate. A collision ensues.
[Set-Up Time: 10 min.]

1D60.3 Water-Jet Parabola
A stream of water is shot beneath an inclined rod and seen to drop away from it parabolically, just touching equally spaced pointers of length 1,4,9, and 16 hanging from the rod. When the inclination of the rod is changed, the displacement of the water stream beneath it remains the same.
[Set-Up Time: 5 min.]

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1F - Newton's First Law

20. Inertia of Rest

1F20.1 Table-Cloth Pull
A table-cloth is pulled out from under a pitcher full of water.
[Set-Up Time: 2 min.]

1F20.2 Mass Suspended from Mass
A 5-lbs weight is suspended by string beneath a 10-lbs. weight, which itself is suspended by string beneath a sturdy support. Although the tension in the top string is initially three times as great, the bottom string will snap if the 5-lbs. weight is pulled suddenly.
[Set-Up Time: 10 min. Has not been successfully set up.]

30. Inertia of Motion

1F30.1 Air Track and Rider
A rider on a frictionless, level air-track moves with constant velocity.
[Set-Up Time: 10 min.]

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1J - Statics of Rigid Bodies

10. Finding Center of Gravity

1J10.1 Center of Gravity of Irregular Shape
An irregularly shaped disk is suspended from a point at its edge, and a plumb bob indicates the vertical line which passes through its center of gravity. The intersection of several such lines then indicates the exact location of the center of gravity. Various shapes are available. See also 1D40.1 Tossing an irregularly Shaped Disk
[Set-Up Time: none]

1J10.2 Meter Stick on Fingers
Slide your fingers together under a meter stick and they automatically meet at the center of gravity. Add a small clamp to one end and repeat.
[Set-Up Time: 5 min.]

11. Exceeding Center of Gravity

1J11.1 Leaning Tower of Lire
Blocks are stacked staircase fashion until the top block sticks out beyond the edge of the bottom block.
[Set-Up Time: 15 min.]

1J11.2 Double Cone Rolling Up Incline
A double cone appears to roll uphill while its center of gravity lowers.
[Set-Up Time: 5 min.]

20. Stable, Unstable, and Neutral Equilibrium

1J20.1 Stability of Block, Cone, and Sphere
[Set-Up Time: 5 min.]

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1K - Applications of Newton's Laws

Dynamic Torque

1K10.10 Tipping Block

A vertical wooden block has multiple strings attached above and below its center of mass. When one of the strings is pulled, the block slides on the table; when the other is pulled, the block topples over.
[Set-Up Time: 5 min.]

20. Friction

1K20.1 Angle of Repose
Adjust the angle of a wooden incline until various objects begin to slide. Then substitute the wooden incline with a teflon one.
[Set-Up Time: 5 min.]

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1M - Work and Energy

10. Work

1M10.1 Pile Driver
Drive a nail into a block of wood by releasing a weight that falls along a track.
[Set-Up Time: 10 min.]

40. Conservation of Energy

1M40.1 Large Pendulum and Nose
Rooms 301 and 428 only -- A fifty-pound weight is suspended from the ceiling of the lecture hall. Standing against the wall, hold the pendulum to your nose, release it, and do not flinch when it swings back.
[Set-Up Time: 10 min.]

1M40.2 Pendulum with Peg
The string of a pendulum is intercepted half-way by a peg, but the bob continues to swing to the same height on the other side.
[Set-Up Time: 5 min.]

1M40.3 Loop the Loop - Hot Wheels Car
A hot-wheels car rolls down a track and around a vertical loop.
[Set-Up Time: 10 min.]

1M40.33 Potential-Kinetic Energy Tracks
Four curved tracks have different slopes but the same height. Balls will leave bottom of structure at the same velocity.
[Set-Up Time: 10 min.]

1M40.4 Loop the Loop - Ball
A ball rolls down between two tracks and then around a vertical loop. Rolling energy--and the fact that the rolling diameter is less than the diameter of the ball--makes the analysis slightly different from the Hot Wheels Car above.
[Set-Up Time: 10 min.]

1M40.5 Spring-Coupled Pendula
Two physical pendula are connected horizontally by a spring. Pull one pendulum back while holding the second one at equilibrium. Release, and the oscillation gradually transfers from the first pendulum to the second. Varying the height of the spring changes the period of the transfer. (Same as 3A70.1 )
[Set-Up Time: 15 min.]

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1N - Linear Momentum

20. Conservation of Linear Momentum

1N20.1 Exploding Riders on Air Track
Two riders on the air track are blown apart by igniting a toy pistol cap. The riders may be of equal or unequal masses; when they return, they stick together and come to rest again.
[Set-Up Time: 15 min.]

22. Rockets

1N22.1 Water Rocket
First launch a toy rocket pumped just with air, then add a little water, pump again, and launch.

30. Collisions in One Dimension

1N30.1 Collision Balls (Newton's Cradle)
Five balls suspended side by side; pull back one, two, or three to demonstrate conservation of momentum and energy.
[Set-Up Time: 5 min.]

1N30.2 Collisions on the Air Track
Riders of equal or unequal masses can engage in elastic collisions.
[Set-Up Time: 10 min.]

1N30.3 Big Ball and Little Ball Drop
A racquet-ball is held above a basketball and both are dropped simultaneously. When this pair hits the floor, the racquet-ball rebounds to many times its initial height.
[Set-Up Time: 5 min.]

40. Collisions in Two Dimensions

1N40.1 Air Table Collisions
Demonstrate elastic collisions with pucks of equal or unequal masses.
[Set-Up Time: 20 min.]


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1Q - Rotational Dynamics

10. Moment of Inertia

1Q10.1 Inclined Plane with Solid and Hollow Cylinders
Race cylinders (or also spheres) with different moments of inertia down an incline.
[Set-Up Time: 5 min.]

1Q10.2 Moment of Inertia Wheels
Two wheels are rotationally accelerated by the falling of equal weights. The two wheels have the same mass but different moments of inertia and consequently accelerate at different rates.
[Set-Up Time: 10 min.]

1Q10.3 Falling Faster than g
A hinged wooden plank with a cup near its middle is lifted at an angle, and a ball is placed at its end. When the plank is released, it falls away faster than the ball and the ball drops into the cup.
[Set-Up Time: 5 min.]

20. Rotational Energy

1Q20.1 Wendell's Wheel
A wheel which is wound up with string around its axle is dropped; it spins rapidly, but descends slowly as almost all of the potential energy gained goes into rotational energy.
[Set-Up Time: 2 min.]

40. Conservation of Angular Momentum

1Q40.1 Rotating Platform and Weights
Stand on a rotating platform while holding two dumbbells far out and bringing them inward.
[Set-Up Time: 5 min.]

1Q40.2 Squeezatron
Squeezing the handle while the two masses are spinning brings them closer together and consequently speeds them up.
[Set-Up Time: 5 min.]

1Q40.3 Rotating Platform and Bicycle Wheel
Turn a spinning bicycle wheel while standing on a rotating platform.
[Set-Up Time: 5 min.]

1Q40.4 Train on Circular Track
A train moves around a circular track which is free to rotate. When started from rest, the train and track move in opposite directions. This demo is old and can be temperamental.

50. Gyroscopes

1Q50.1 Bicycle Wheel Gyroscope
A spinning bicycle wheel suspended on one side demonstrates precession. Can either be hand held or, in Rooms 301 and 428, suspended from the ceiling.
[Set-Up Time: 10 min.]

1Q50.2 Gyroscope
A standard three-frame gyroscope. Both large and small sizes available.
[Set-Up Time: 2 min.]

1Q50.3 "Floating on Air" (Air-Bearing) Gyroscope
A large bearing spins freely on a cushion of air. The bearing has a rod attached, which makes it easy to demonstrate precession and nutation.
[Set-Up Time: 5 min.]

60. Rotational Stability

1Q60.30 Tippe Top
When spun, the tippe top flips upside down, spinning on its handle.
[Set-Up Time: 5 Min.]

1Q60.36 Spinning Eggs
A wooden egg spun on its side (short axis) flips up to spin on its long axis. If it is spun on a board, the board can be picked up and rotated in the opposite the egg, driving the egg to continue spinning indefinitely.
[Set-Up Time: 5 Mins.]

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1R - Properties of Matter

10. Hooke's Law

1R10.1 Hooke's Law
Show that the displacement of a spring is proportional to the applied force, using spring scales or springs of different spring constants.
[Set-Up Time: 5 min.]

40. Coefficient of Restitution

1R40.1 Happy Ball and Unhappy Ball
Two rubber balls, apparently similar except that one bounces while the other doesn't.

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