Question

A Cannon makes a noise, and it's echo is heard 4.5 seconds later. if sound travels at 343 m/s:

a.) how far did the sound travel?

b.) how far away is the surface it reflected off of?

Answer 1

a).  (343 m/s) x (4.5 sec)  =  1,543.5 meters

b).  The surface it reflected from is  (1543.5 / 2) = 771.75 meters away.

     The sound had to go there AND come back before you heard the echo.