A fisherman uses high-frequency sound waves to find fish in the sea. Fig. 8.1 shows the waves as they are sent out from the boat. The diagram labels are: fishing boat, sound waves, seabed.
(a)[1]
State the name given to sound waves whose frequency is greater than $20\,\text{kHz}$.
(b)[3]
Calculate the time taken for the boat to detect the wave reflected from the seabed after the sound is sent out.
(c)[2]
Describe and explain how the reflected sound wave received by the boat from the fish is different from the reflected sound wave received from the seabed.
Worked solution & mark scheme
This 6-mark question has a full step-by-step worked solution and mark scheme. One marking point: “Ultrasonic waves” …