Magnitude

A logarithmic scale

An interactive lesson with 7 steps, about 6 minutes: you predict, drag and solve, with instant feedback on every answer. It runs in your browser and needs JavaScript.

What you’ll learn

• Magnitude is logarithmic.
• Each step: about 10× amplitude and about 32× energy.
• Two steps: about 1,000× the energy.

Steps

1. Steps of ten
2. Energy comparison
3. The biggest ever
4. Big quakes are rare
5. Where’s the energy?
6. Many small, few big
7. Small change, big difference