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Factors affecting speed of sound in air
The speed of sound in air under normal conditions is about 330m/s. However, this can change depending on the prevailing factors as illustrated below:
- Temperature of the air: warm air is lighter than cold air. An increase in the temperature of air causes an increase in the speed of the sound.
- Wind: if wind blows in the direction of the sound, its speed will be raised while if it blows against the sound, the speed will be reduced.
- Humidity: the speed of sound increases with humidity. Moist air having water vapour in it is less dense compared to dry air. An increase in the humidity of the air makes the air lighter and hence the speed of the air is increased.
- Density of air: the greater the density of air the lower its speed.
Not that as long as the temperature of air is constant, there is no effect of changing pressure on the speed of sound.
- Nature of transmitting medium – different substances transmit sound waves at various speeds as shown below
(i) Air – 346 m/s
(ii) Hydrogen – 1339 m/s
(iii) Water – 1498 m/s
(iv) Aluminium – 5,000 m/s
(v) Iron – 5,200 m/s
(vi) Glass – 4,540 m/s
Moraa orina answered the question on April 8, 2018 at 10:07
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