Question

What instruments are used to measure the strength of earthquakes?

Answer 1

An earthquake has one magnitude unit. The magnitude does not depend on the location where the measurement is made. A seismograph is a primary earthquake measuring instrument. The seismograph produces a digital graphic recording of the ground motion caused by the seismic waves. The digital recording is called a seismogram. the earthquake magnitude scale was the Richter scale, a mathematical formula invented by Caltech seismologist Charles Richter to compare quake sizes.