Six seconds after a lightning flash was seen, thunder was heard. How far was the lightning if the temperature was 30ᵒC?
Dolphins emit very short sound waves with a frequency of 2510^5 cycles per second. What is their wavelength in water? (Assume that the velocity of sound in seawater is 1520 m/s)
What is the speed of sound at 20ᵒ and normal atmospheric pressure?
Dolphins emit very short sound waves with a frequency of 2510^5 cycles per second. What is their wavelength in water? (Assume that the velocity of sound in seawater is 1520 m/s)
What is the speed of sound at 20ᵒ and normal atmospheric pressure?
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The speed of sound at 30ºC in dry air is 20.05*√[30*273] = 349 m/s. The distance is then 6*349 = 2.1 km
The period is 1/f = 4*10^-7 sec^-1 The wavelength is the distance traveled in one period = 1520*4*19^-7 = 0.00061 m = 0.61 mm
The speed of sound at 20 ºC and 1 atm is 343.2 m/s
The period is 1/f = 4*10^-7 sec^-1 The wavelength is the distance traveled in one period = 1520*4*19^-7 = 0.00061 m = 0.61 mm
The speed of sound at 20 ºC and 1 atm is 343.2 m/s