Properties of Ultrasonic Waves
Properties of Ultrasonic Waves
Infrasonic Sound: The sound of frequencies lower than 20 Hz are known as infrasonic sounds or infrasound, which cannot be heard by human beings. Earthquakes and some animals like whales, elephants and rhinoceroses produce infrasonic sound of frequency 5 Hz. It is observed that some animals get disturbed and start running here and there just before the earthquakes occur. This is because earthquakes produce low frequency infrasound before the main shock waves begin which possibly alert the animals and they get disturbed
Ultrasonic Sound: The sounds of frequencies higher than 20000 Hz are called ultrasonic sounds or ultrasounds which cannot be heard by human beings. Dogs can hear ultrasonic sounds of frequency to 50,000 Hz. This is why dogs are used for detective work by the police. Monkeys, bats, cats, dolphins, leopard and porpoises can also hear ultrasonic sounds.
Bats make use of _____ waves. | |||
| Right Option : A | |||
| View Explanation | |||
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| Right Option : A | |||||||||||||
| View Explanation | |||||||||||||
Which of the following are correct : (a) The sound of frequencies lower than 20 Hz are known as infrasonic sounds. (b) The sound of frequencies lower than 200 Hz are known as ultrasonic sounds. (c) The sounds of frequencies higher than 20000 Hz are called ultrasonic sounds. | |||
| Right Option : C | |||
| View Explanation | |||
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