Richter scale is used for measuring

The correct answer is D. Intensity of earthquakes.

The Richter magnitude scale, also known as the Richter scale, measures the magnitude of earthquakes by measuring the amplitude of seismic waves recorded by seismographs. The scale is logarithmic, so an earthquake that measures 6.0 on the Richter scale is 10 times more powerful than an earthquake that measures 5.0.

The Richter scale was developed in 1935 by Charles Francis Richter and Beno Gutenberg. It is the most common scale used to measure the magnitude of earthquakes.

The other options are incorrect because:

• The density of a liquid is measured by its mass per unit volume.
• The humidity of air is measured by the amount of water vapor in the air.
• The velocity of wind is measured by the speed at which the wind is blowing.