Question

8. How do the following use echoes?

(c) fishermen

Answer 1

Step 1:

• Fishermen uses echo sound for locating the presence of fishes in the sea.
• The ultrasonic vibrator produces ultrasonic sound waves to propagate into the water.
• When the vibrations strikes the fishes, receivers are enabled to receive the reflected vibrations.

Step 2:

• The time travel of echoes are recorded.
• Distance between trawler and fish is calculated by, $d=\frac{v\times t}{2}$
• $v$- Velocity of sound in water.
• $t$- Time taken by echo to travel back to the trawler.