Question

A sonar echo returns to a submarine \(1.20\;{\rm{s}}\) after being emitted. What is the distance to the object creating the echo? (Assume that the submarine is in the ocean, not in fresh water.)

Short answer

The distance to the object creating echo is \(206\;{\rm{m}}\).

Step-by-step solution

Echo

The reflected sound reaches the listener separately from the primary source, an echo.

Given Data

The time of travel is \(T = 1.20\;{\rm{s}}\).

Calculation of the distance

The distance of the object creating echo is given by,

\(d = 0.5vT\)

Here,\(v = 343\;{\rm{m/s}}\)is the speed of sound in air.

Plugging the values,

\(\begin{align}d &= 0.5 \times 343 \times 1.20\\ &= 206\;{\rm{m}}\end{align}\)

Therefore, the distance to the object creating the echo is \(206\;{\rm{m}}\)