- Sections
- A. General Materials & Mathematics
- B. Statics
- C. Kinematics & Dynamics
- D. Rotational Mechanics
- E. Gravitation & Astronomy
- F. Fluid Mechanics
- G. Vibrations & Mechanical Waves
- H. Sound
- I. Thermodynamics
- J. Electrostatics & Magnetostatics
- K. Electromagnetic Principles
- L. Geometrical Optics
- M. Wave Optics
- N. Spectra & Color
- O. Vision
- P. Modern Physics
Coupled Pendula - 100 To 1 Mass Ratio
Purpose
To illustrate mechanical resonance.
Equipment
Two pendula hanging in series from a fixed point as photographed.
Suggestions
This idea is used to amplify the oscillation of a gravitational wave antenna bar so that it can then be sensed by a sensitive transducer or by laser interferometry techniques.
Images
Description
The two pendula have the same length, but the mass of the upper bob is 100 times that of the lower bob. With the masses hanging motionless, gently tap the bigger mass. Its energy will couple to the smaller mass, causing the smaller mass to oscillate with a much larger amplitude. The energy then couples back to the larger mass, and the cycle repeats.◙
References
J. -P. Richard, Approaching the Quantum Limit with Optically Instrumented Multimode Gravitational-Wave Bar Detectors,
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See pagesg1. simple harmonic motion
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See pagesg2. resonance & coupled oscillations
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See pagesg3. mechanical waves one dimensional
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See pagesg4. mechanical waves two dimensional
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See pagesg1. simple harmonic motion
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See pagesg2. resonance & coupled oscillations
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See pagesg3. mechanical waves one dimensional
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See pagesg4. mechanical waves two dimensional