Sonar is a device that uses ultrasonic waves to measure the distance, direction, and speed of objects underwater.
In the figure, ultrasonic waves are sent out from a SONAR which is installed in a ship and they get reflected back after striking an object at the bottom of the sea.
(i) What happens to the ultrasonic waves after striking the object on the seabed?
(ii) The distance traveled by a wave can be calculated by knowing the speed of ultrasonic sound in seawater and the time taken for the wave to return.
(iii) Ultrasonic waves from a ship hits a rock at the bottom of the sea and comes back after 0.5 s. Calculate the distance to the rock from the ship. Consider speed of sound through seawater as 1522 m/s.
(iv) Bats make use of ultrasonic sounds for catching prey. How do bats catch prey? Observe figure and write down in your science diary.
(i) Ultrasonic waves that are reflected back after striking the object reach the detector. The detector converts the ultrasonic waves into electrical signals.
(ii) Distance = speed × time
(iii) Distance = speed × time .
= 1522 x \(\frac{0.5}{5}\) = 380.5 m
(iv) Bats produce ultrasonic sounds and the sound gets reflected after striking the prey. It can receive the waves.