Advertisements
Advertisements
Question
Define the following terms : (a) Echolocation (b) Echocardiography, and (c) Ultrasonography.
Advertisements
Solution
(i) Echolocation: It is the method used by some animals to locate the objects by hearing the echoes of their ultrasonic squeaks. This method is used by bats and dolphins in finding their way and detecting their prey.
(ii) Echocardiography is a method used to investigate the action of the heart by using ultrasound waves.
(iii) Ultrasonography is a technique of obtaining pictures of internal organs of the body by using echoes of ultrasound pulses.
APPEARS IN
RELATED QUESTIONS
A submarine emits a sonar pulse, which returns from an underwater cliff in 1.02 s. If the speed of sound in salt water is 1531 m/s, how far away is the cliff?
Explain how bats use ultrasound to catch a prey.
A sonar device on a submarine sends out a signal and receives an echo 5 s later. Calculate the speed of sound in water if the distance of the object from the submarine is 3625 m.
How does the pitch of a sound depend on frequency ?
Name the characteristic of sound which depends on (a) amplitude (b) frequency, and (c) waveform.
Name the characteristic of sound which can distinguish between the 'notes' (musical sounds) played on a flute and a sitar (both the notes having the same pitch and loudness).
What name is given to sound waves of frequencies higher than 20 kHz ?
Draw labelled diagrams to represent (a) soft sound, and (b) loud sound, of the same frequency.
Explain why, if we strike a table lightly, we hear a soft sound but if we hit the table hard, a loud sound is heard.
Explain how, flaws (or defects) in a metal block can be detected by using ultrasound.
