Astrophysical Principles - Radiation

Inverse Square Law

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Large climbing frame shaped to show inverse square relation of light intensity (smaller version also available).

Tower of Spectra

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Assembly of three gas discharge tubes and white light source for spectral analysis with diffraction gratings.
[In-Depth Description]

Sodium Absorption

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Burning of sodium bicarbonate in Bunsen flame produces sodium absorption lines in continuous spectrum.
[In-Depth Description]

Boltzmann Distribution

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Mechanical analog of energy level populations which models a gas at essentially any temperature.

Collisional Broadening

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Na D-doublet absorption lines broaden into one large absorption band due to increase in pressure/temperature.
[In-Depth Description]

Spectrum Piano

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The visible part of the electromagnetic spectrum is represented by less than an octave of the keys; UV, IR, and microwaves are also indicated.
[In-Depth Description]

Relativity Train

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Demonstration of time dilation and length contraction gedanken experiment using a train on a track.
[In-Depth Description]

Bouncing Photon

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A photon (modeled by a bouncing ping-pong ball) is observed from two reference frames and provides the motivation for time dilation.
[In-Depth Description]

Doppler Ball

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Plastic Wiffle Ball with built-in shriek to throw past (or at) your audience.
[In-Depth Description]

Doppler Turntable

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Two speakers, one at each end of rotating platform; beating due to frequency shift of speakers travelling in opposite directions.
[In-Depth Description]

Doppler Whirler

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A high-pitched alarm on the end of a rope is whirled about the head.
[In-Depth Description]

Doppler Tuning Forks

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Run towards the blackboard carrying a tuning fork...
[In-Depth Description]

Doppler Effect

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Listen to the doppler shift of light as a moving mirror reflects laser light onto a photodetector.

Elastic Light

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Wave drawn on elastic sheet shows redshift due to expansion of space.
[In-Depth Description]

Contact Us

Mailing Address: Lecture Demonstration Services, Science Center, Rm B-08A, 1 Oxford Street, Cambridge, MA 02138
Campus Location: Science Center B-08A | Tel: (617) 495-5824 | Email: scidemos-at-fas.harvard.edu