Question

A sound wave traveling downward with a speed of about 4,000 m/s suddenly slows to 1,500 m/s not far below the earth’s surface. what has the sound wave most likely encountered?

Answer 1

Answer: an underground lake

Explanation:

I took the test

Answer 2

speed of sound wave depends on elasticity of medium and density of medium

it is given by formula

$v = \sqrt{\frac{E}{/rho}}$

now if wave travel through solid then its speed is maximum while if it travel from gas then its speed is minimum

so initially its speed is given as 4000 m/s and suddenly decrease to 1500 m/s

so here we can say that its medium will change from solid to liquid

so sound will encounter with water