(a) What is meant by the (a) 'pitch' of sound, and (b) 'quality' of sound?
(b) What is ultrasound? State two uses of ultrasound.
(a) What is meant by the (a) 'pitch' of sound, and (b) 'quality' of sound?
(b) What is ultrasound? State two uses of ultrasound.
(a) Pitch: Pitch is the characteristic of a wave by which sound wave appears shrill or grave. It depends upon the frequency of the wave.
Higher the frequency higher will be the pitch and vice-versa.
Frequency and hence the pitch of a female voice is more than the frequency and the pitch of a male voice and hence female voice is shrill and male voice is grave.
Quality: It is the sensation received by the ear by which, we are able to differentiate two sounds (even if they are of same pitch and loudness).
The quality actually depends on the shape of the waveform and the number of overtones.
e.g. the two waveforms shown in the figure are of the same frequency and same amplitude, but since their shape is different they will have different quality.
We differentiate the sound of a mouth organ and guitar because of different quality. A pleasant sound has certain well-defined frequencies which have considerable amplitudes.
(b) Ultrasounds are sound waves with frequencies higher than the upper audible limit of human hearing. Ultrasound is not different from "normal" (audible) sound in its physical properties, except in that humans cannot hear it. This limit varies from person to person and is approximately 20 kilohertz (20,000 hertz) in healthy young adults. Ultrasound devices operate with frequencies from 20 kHz up to several gigahertz.
Ultrasound is used in many different fields. Ultrasonic devices are used to detect objects and measure distances. Ultrasound imaging or sonography is often used in medicine. In the nondestructive testing of products and structures, ultrasound is used to detect invisible flaws. Industrially, ultrasound is used for cleaning, mixing, and to accelerate chemical processes.
Uses
1:-Detection of developmental/ structural abnormalities in the fetus
2:-Diagnosis of gallbladder disease/ obstruction
3:-Evaluation of blood flow in blood vessels
(a) Pitch: Pitch is the characteristic of a wave by which sound wave appears shrill or grave. It depends upon the frequency of the wave.
Higher the frequency higher will be the pitch and vice-versa.
Frequency and hence the pitch of a female voice is more than the frequency and the pitch of a male voice and hence female voice is shrill and male voice is grave.
Quality: It is the sensation received by the ear by which, we are able to differentiate two sounds (even if they are of same pitch and loudness).
The quality actually depends on the shape of the waveform and the number of overtones.
e.g. the two waveforms shown in the figure are of the same frequency and same amplitude, but since their shape is different they will have different quality.
We differentiate the sound of a mouth organ and guitar because of different quality. A pleasant sound has certain well-defined frequencies which have considerable amplitudes.
(b) Ultrasounds are sound waves with frequencies higher than the upper audible limit of human hearing. Ultrasound is not different from "normal" (audible) sound in its physical properties, except in that humans cannot hear it. This limit varies from person to person and is approximately 20 kilohertz (20,000 hertz) in healthy young adults. Ultrasound devices operate with frequencies from 20 kHz up to several gigahertz.
Ultrasound is used in many different fields. Ultrasonic devices are used to detect objects and measure distances. Ultrasound imaging or sonography is often used in medicine. In the nondestructive testing of products and structures, ultrasound is used to detect invisible flaws. Industrially, ultrasound is used for cleaning, mixing, and to accelerate chemical processes.
Uses
1:-Detection of developmental/ structural abnormalities in the fetus
2:-Diagnosis of gallbladder disease/ obstruction
3:-Evaluation of blood flow in blood vessels
