Name the sounds of the frequencies given below :
(a) 10 Hz
(b) 100 Hz
(c) 1000 Hz
(d) 40 kHz
(a) Infrasonic (b) Audible (c) Audible (d) Ultrasonic.
What name is given to sound waves of frequencies higher than 20 kHz?
A source of sound emitting a note of frequency 200 Hz moves towards an observer with a velocity v equal to the velocity of sound. If the observer also moves away from the source with the same velocity v, the apparent frequency heard by the observer is