How many meters away is a cliff if an echo is heard $\frac{1}{2}$ $1/2$ second after you yell hello?

Question

Assume that sound travels at 343 m/s.

2747 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2017-07-23T18:22:21

$85, 75$ $85,75$ m

So the sound to reach you must travel $x$ $x$ m to the cliff and then
$x$ $x$ m back to you. The sound travels with a constant speed so :

$d = v t \Rightarrow 2 x = v t \Rightarrow x = \frac{v t}{2} = \frac{343}{4} = 85, 75$ $d=vt=>2x=vt=>x=(vt)/2=343/4=85,75$ m