Practice Test 4

A seismic sensor records two surface waves from different earthquakes at the same station. Event 2 produces a ground-displacement amplitude that is 5 times larger than Event 1 ($A_2 = 5A_1$), with similar frequency content. Using $E \propto A^2$, what is the energy ratio $E_2/E_1$ carried by the wave?

A wave pulse travels along a string with amplitude $A_1 = 3\ \text{cm}$. A second pulse on the same string (same tension and speed) has amplitude $A_2 = 6\ \text{cm}$. If the energy carried by a string wave is proportional to amplitude squared ($E \propto A^2$), what is the ratio $E_2/E_1$?