1A50.20 - Optical Lever Arms

Code Number:
Demo Title:
Optical Lever Arms
Magnification of small movements.
Area of Study:
Clock with mirror mounted on the hour hand, laser pointer.

Place a battery in the clock and lay it flat on a table.  Point the laser pointer at the mirror and adjust so that the beam falls onto a distant wall or screen.  Most people are surprised to notice that the spot will travel about 6 to 9 inches per minute.

  • Erlend H. Graf, "Physics for Poets?", TPT, Vol. 43, # 2, Feb. 2005, p. 118 - 119.

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