Question

Give Scientific reasons - don't use lifts at the time of earthquake.

Answer 1

During an earthquake it is unsafe to use a lift because an elevator may get stuck and put the person inside in danger as ther is always the chance that the lift may plummet or may be crushed by debris of the building.

Answer 2

During an earthquake several seismic waves are emitted from the source which include body waves like P and S waves and surface waves like Rayleigh and Love wave.

Most damage is caused by the latter two waves.

The Love waves undergo geometric dispersion and the phase velocity increases monotonically.

These effects damages all the machines that are near to the surface such as the lift motor room.

Hence during an Earthquake it is better not to ride an elevator or lift.