Sound Navigation and Ranging (SONAR) is used to detect underwater objects. For this, its transmitter produces
ultrasonic waves
SONAR works on the principle of echo-ranging: the transmitter sends out sound pulses that travel through water, reflect off an underwater object, and are picked up by a receiver, and the time delay is used to calculate the object's distance.
Since these sound pulses must have a frequency far above the range of human hearing (above about 20 kHz) to give sharp, focused beams and better resolution underwater, the transmitter produces ultrasonic waves rather than microwaves, visible light or infrared, which do not travel efficiently through water for this purpose.
Hence, the answer is ultrasonic waves.
Which of the following is correct?
I. Sound is a mechanical wave
II. Sound wave does not need any medium to propagate
At a particular temperature, sound propagates in ______ at the fastest speed .
The atmospheric green house effect is produced mainly by the absorption and re-emission of:
Which of the following are examples of electromagnetic waves?
a. Television waves
b. Ultraviolet rays
c. X-rays
d. Sun rays
When light passes from one medium into another medium, then the physical property which does not change is