Which option correctly expresses the approximate energy multiplier for a two-point increase on the Richter scale?

Which option correctly expresses the approximate energy multiplier for a two-point increase on the Richter scale?

• A. About 100 times
• B. About 1000 times
• C. About 31.7 times
• D. About 2 times

Answer: (B)

The energy released by earthquakes grows very quickly because the magnitude scale is logarithmic. Each unit increase in magnitude corresponds to roughly a 31.6-fold increase in energy. So for a two-point rise, you multiply that energy increase twice: 31.6 × 31.6 ≈ 1000. In other words, a two-unit jump releases about a thousand times more energy. That’s why the best choice is about 1000 times.

The energy released by earthquakes grows very quickly because the magnitude scale is logarithmic. Each unit increase in magnitude corresponds to roughly a 31.6-fold increase in energy. So for a two-point rise, you multiply that energy increase twice: 31.6 × 31.6 ≈ 1000. In other words, a two-unit jump releases about a thousand times more energy. That’s why the best choice is about 1000 times.