UPSC CSE Prelims 2001 Q59 — Geography PYQ with Answer

Consider the following statements regarding earthquakes:

I. The intensity of an earthquake is measured on the Mercalli scale.

II. The magnitude of an earthquake is a measure of energy released.

III. Earthquake magnitudes are based on direct measurements of the amplitude of seismic waves.

IV. In the Richter scale, each whole number demonstrates a hundred-fold increase in the amount of energy released.

Which of these statements are correct?