A person with her ear to the ground sees a huge stone strike some concrete pavement. A while later she hears two sounds from the impact: One travels in air and the other in concrete, and they are 1.1 s apart. The speed of sound in air is 343 m/s and in concrete is 3000 m/s. The distance from the point of impact is

Question

Quizplus · Accepted Answer

The time difference between the sounds is due to the different speeds of sound in air and concrete. Using the formula for distance, $d = vt$, and the given speeds, we can set up the equation: $d/343 - d/3000 = 1.1$. Solving for $d$ gives approximately 430 meters, or 0.43 km.

A Person with Her Ear to the Ground Sees a Huge