Question

The diagram in Fig. shows the displacement- time graph of a vibrating body. Give one example of such vibrations.

Answer 1

The harmonic oscillations at varying amplitude, oscillating are shown in Figure between $-aand+a$. Harmonic oscillations tend to die away as time goes on. This behaviour, called damping of the oscillations, is produced by forces such as friction and viscosity. These forces are known collectively as dissipative forces because they tend to dissipate the potential and kinetic energies of macroscopic bodies into the energy of the chaotic motion of atoms and molecules known as heat.
Hence, the vibrations are damped vibrations.
Example - Vibration damping is a term that is used in industrial, electronic and ergonomic applications when there is a need to reduce the amount of energy that is produced by the system. Normally engineers try to address and reduce this energy at its source so the disturbing force is not at or near a natural frequency. This will ensure that resonance does not occur. Sometimes this is not possible for many reasons so problems will usually be controlled with a vibration damper. Usually when a good vibration damper is added, the energy that is left over is removed and converted to a small amount of heat which is referred to as the swallowed energy.