Question

what is infrasonic waves and ultrasonic waves.... please help mee..;... please

Answer 1

Infrasonic waves:- Sound waves with frequencies less than 20 Hz are known                                  as infrasonic waves. such waves are produced by large                                     vibrating bodies.

Ultrasonic waves:- Sound waves with frequencies more than 20,000 Hz are                                    known as ultrasonic waves of ultrasound. Bats, dog, rats                                    can produce and also listen these waves

Answer 2

INFRASONIC WAVES----->
 The waves having frequencies lower than 20Hz are known as infrasonic waves .You can take the example of earthquakes.
You might have noticed animals getting disturbed and start running before an earthquake occurs.
 Earthquakes produce low infrasonic waves before the main shock waves. So there are some animals that can hear these infrasonic waves and they get disturbed.

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ULTRASONIC WAVES ------->
The waves having frequencies of more than 20,000Hz are called ultrasonic waves.Police take the help of dogs while any investigation or any detective work.
This is because dogs can hear ultrasonic sounds upto 50,000Hz. Bats, dolphins are other animals who can hear the ultrasonic sounds