(a) What do you understand by the term ‘ultrasonic vibration’? (b

1.	(a) What do you understand by the term ‘ultrasonic vibration’? (b) State three uses of ultrasonic vibrations. (c) Name three animals which can hear ultrasonic vibrations
Answer» (a) Ultrasonic Vibration: The vibrations whose frequencies are greater than 20000 Hz are called ultrasonic vibrations. (b) (i) They are used in SONAR to measure the depth of the sea (or ocean) and to locate underwater objects. (ii) It is used for scanning and imaging the position and growth of a foetus and presence of stones in the gall bladder and kidney. (iii) It is used for homogenising milk in milk plants where fresh milk is agitated with the desired quantity of fat and powdered milk to obtain toned milk. (c) Mosquito, Dogs and Bats are the three animals that can hear ultrasonic vibrations.

(a) What do you understand by the term ‘ultrasonic vibration’? (b) State three uses of ultrasonic vibrations. (c) Name three animals which can hear ultrasonic vibrations

Answer»

(a) Ultrasonic Vibration: The vibrations whose frequencies are greater than 20000 Hz are called ultrasonic vibrations.

(b)

(i) They are used in SONAR to measure the depth of the sea (or ocean) and to locate underwater objects.

(ii) It is used for scanning and imaging the position and growth of a foetus and presence of stones in the gall bladder and kidney.

(iii) It is used for homogenising milk in milk plants where fresh milk is agitated with the desired quantity of fat and powdered milk to obtain toned milk.

(c) Mosquito, Dogs and Bats are the three animals that can hear ultrasonic vibrations.

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