Earthquakes and Resonance

Which of the labels at left indicates the amplitude of the wave?

Which of the labels at left indicates the period of the wave?

What is the period of this building's oscillation (back-and-forth movement)?

Hint: It makes 12 back-and-forth motions in 4 seconds.

After allowing a pendulum to swing back and forth 10 times, you determine that the period of the pendulum is 2 seconds. What is its frequency?

Very tall buildings have ___ natural frequencies compared to very short buildings.

A skyscraper should be built on

We saw in the lecture today that this is the equation that relates the natural frequency of a building to its length and the acceleration due to gravity. If we make a building 4 times taller than the original, how will this change the natural frequency?

$$f\propto\sqrt[]{\frac{g}{L}}$$