Question

The rear view mirror of a motorbike starts vibrating violently at some particular speed of motorbike. Why does it happen ?

Answer 1

The rear view mirror of a motorbike starts vibrating violently at some particular speed of motorbike due to resonance. When bike runs at particular speed it produces some vibrations coming from the engine of the bike which puts pressure on the shocks of the bike which causes the violent vibrations in the bike also when frequency of vibrations of engine of the motorbike becomes equal to the natural frequency of vibration of the rear view mirror. The amplitude of vibration of the mirror becomes maximum which results in vibrating violently.