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Question
The rearview mirror of a motorbike starts vibrating violently at some particular speed of the motorbike, what could be done to stop the violent vibrations.
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Solution 1
This can be stopped by mounting the engine on such a structure, say steel springs that absorb the vibrations of the engine without communicating them to the frame and in this condition, the rearview mirror attached to the frame will not vibrate violently.
Solution 2
(i) The frame of a motorcycle along with the rearview mirror is found to vibrate violently when it is driven to a particular speed. This happens when the frame has the natural frequency of vibration equal to that of the piston when the engine is driven at that particular speed.
(ii) This phenomenon is called ‘resonance’. In this phenomenon when a body begins with the natural frequency of the others vibrating body B, then A begins to vibrate violently with the maximum amplitude.
(iii) This can be stopped by mounting the engine on such a structure, say steel springs that absorb the vibrations of the engine without communicating them to the frame and in this condition, the rearview mirror attached to the frame will not vibrate violently.
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