What is the range of frequencies associated with (a) Infrasound? (b) Ultrasound?

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Chapter 11 NCERT Class 9 Science SOLUTIONS

2. What is the range of frequencies associated with (a) Infrasound? (b) Ultrasound?

Question:

What is the range of frequencies associated with

(a) Infrasound?

(b) Ultrasound?

Answer:

(a) The sound of frequency less than 20 Hz are called infrasound.

(b) The sound of frequency above 20 KHz or 20,000 Hz are called ultrasound.

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