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Questions
Differentiate between the forced and resonant vibrations.
State two differences between forced and resonant vibrations.
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Solution
| Forced Vibrations | Resonant vibrations |
| These are vibrations of a body under an external periodic force of frequency different than the body's natural frequency. | These are vibrations of a body under an external periodic force of frequency exactly equal to the natural frequency of the body. |
| The amplitude of the vibration is usually small. | The amplitude of vibration is very large. |
| The body's vibrations are not in phase with the external periodic force. | The vibrations of the body are in phase with the external periodic force. |
| These vibrations last very short after the periodic force has ceased to act. | These vibrations last long after the periodic force has ceased to act. |
Notes
Students should refer to the answer according to their questions.
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