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An earthquake is movement of earth crust.

The surface beneath the earth is formed of plates.

When these plates collide with each other, an earthquake is emerged.

The strength or magnitude of earthquake is measured using Richter Scale. Which is measured from 1 to 9.

The magnitude of earthquake differs form small to high.

A magnitude below 5 scale is considered as small and mostly is not harmful.

However, a magnitude above 5 or above is considered as dangerous. As it may case damage to buildings and life.