Question

A sonar signal sent down from ship, is reflected from the ocean floor and detected by a hydrophone 0.6 s later. Calculate the depth of the ocean.

Take the speed of sound in sea water as $1500m{s}^{-1}$

Answer 1

Step 1 Given,

1. Time $\left(t\right)=0.6s$
2. speed of sound in the sea $\left(s\right)=1500m/s$
3. depth of the ocean $\left(d\right)=?$

Step 2 Formula used,

1. Time taken by the echo to come back =$\frac{2\times dis\tan ce}{speedofsound}$
2. Speed of sound = $\frac{2xDis\tan ce}{Time}$

Step 3 Solution,

$$\begin{gathered} 1500\times 0.6=2\times depth \\ depth=\frac{1500\times 0.6}{2} \\ =\frac{900}{2} \\ =450m \end{gathered}$$

Hence, the depth of the sea is $450m$.