Question

For the Richter scale, each increase on the scale represents ten times the amount of ground motion recorded on the seismogram. How much more motion is there for a magnitude 7 earthquake than a magnitude 4 earthquake?

A) 3 times
B) 30 times
C) 1000 times
D) 3000 times

Answer 1

On the logarithmic Richter scale, a magnitude 7 earthquake has 1000 times more ground motion than a magnitude 4 earthquake.

Step-by-step explanation:

The question asked is about how much more ground motion is produced by a magnitude 7 earthquake compared to a magnitude 4 earthquake on the Richter scale. Since the Richter scale is logarithmic, each whole number increase on the scale means that the ground motion is 10 times greater. Therefore, a magnitude 7 earthquake has 10 times the motion of a magnitude 6, 100 times the motion of a magnitude 5, and consequently, 1000 times the motion of a magnitude 4 earthquake. The correct answer is C) 1000 times.