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K2-44. Eddy Current Pendulum
Purpose
To show damping of pendula due to eddy currents.
Purpose
Eddy current magnet with various pendula.
Suggestions
For an extremely dramatic effect, dip the bob into liquid nitrogen before letting it swing; it stops IMMEDIATELY!
Images
Description
Pendula with bobs of different materials and geometries are swung through the poles of a strong horseshoe magnet. The amount of damping is greater for those bobs in which strong eddy currents can flow. Bobs include, solid copper,copper loop, broken copper loop, laminated copper, copper with central hole, and wood.
References
Francis X. Hart and Kenneth W. Wood, Eddy current distributions: Their calculation with a spreadsheet and their measurement with a dual dipole antenna probe, AJP 59, 461-467 (1991)
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See pagesk1. forces on moving charges
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See pagesk2. electromagnetic induction
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See pagesk3. transformers
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See pagesk4. motors & generators
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See pagesk5. electrical properties of matter
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See pagesk6. electric circuits & instruments
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See pagesk7. rlc circuits
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See pagesk8. electromagnetic waves
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See pagesk1. forces on moving charges
-
See pagesk2. electromagnetic induction
-
See pagesk3. transformers
-
See pagesk4. motors & generators
-
See pagesk5. electrical properties of matter
-
See pagesk6. electric circuits & instruments
-
See pagesk7. rlc circuits
-
See pagesk8. electromagnetic waves