Currently we provide two different versions of this experiment. One version uses balls rolling down a long, inclined track (roughly 2 meters), and the other version uses balls that swing on a pendulum.
Single air track glider, with and without variable frequency driver, variable damping, and oscilloscope position vs. time display.
What It Shows
With one end of the car attached via a spring to the end of the track and the other end of the car coupled (via a similar spring) to a driving motor, we can see how the car behaves when it is driven below, at, and above the resonance frequency. Markings on the motor help to show the phase relationships between the driver and car at different frequencies. A storage scope tracks the motion of the car (see Setting It Up...
Bell plates are polygonal-shaped flat pieces of sheet metal which, when held in the hand and struck with a beater, produce a pleasant, sustained, slightly bell-like tone. Compare this to any arbitrary shaped piece of metal which produces a "clunk" when struck. The sound of the bell plate depends strongly on its shape and even the most modest change in the symmetry (like snipping off a corner) or proportions will make it go clunk when struck.
A 60 Hz AC magnetic flux from an iron core induces an emf in a suspended coil of wire. With appropriate capacitance added, the coil will be attracted to, repelled from, or not affected by the magnetic flux.
All components in the kit are magnetically attached to the blackboard. The light source produces a grazing pencil of light on the surface of the board which may be refracted through, or reflected from, the various optical components. Single...
Black body radiators in thermal equilibrium should emit the same spectrum of radiation, so inside a kiln at high temperature objects should appear the same color whatever their material.
How it works:
Place a piece of brick and an iron ball into a kiln (ours is a Blue M Electric Co. kiln with 25cm × 12cm × 10cm oven) that has a temperature range up to around 1000°C. Close the door and crank up the temperature to maximum. Depending on the type of kiln, it will take around 20 minutes to reach equilibrium (a good length...
The strength of a material in tension or compression will be affected by discontinuities in its surface structure. This can be demonstrated for glass using microscope slides, and the comparison of failure stress before and after the removal of surface scratches.
How it works:
The slide rests between two custom built test beds (figure 1), the upper bed supporting the load. We use slotted 1kg and 0.5kg masses placed carefully in their holder, and allowing a short time between additions. We find the breaking...
A magnesium ribbon is held with tongs and lit with a match or torch, making a bright flame that consumes the ribbon from the bottom up.
The ribbon should be about 20-30 cm long. Hold the ribbon with the tongs high and at arms length. Let the magnesium ribbon hang at a steep angle but not vertical. Light the bottom of the ribbon by bringing the end of the torch flame up to ribbon. Magnesium will melt before it lights, so carefully with the torch. The ribbon can also be lit with a wooden match.
Wear safety glasses and don't look directly at the flame.