Effect of rain on velocity of sound

AI Thread Summary
Heavy rain, described as "cats and dogs," has minimal impact on the velocity of sound in air, primarily because raindrops are small and numerous but do not significantly alter the air's molecular weight. The velocity of sound is mainly influenced by temperature and humidity, with humidity's effect being temperature-dependent. While raindrops do not change sound speed, they can scatter and absorb sound waves, affecting sound propagation over distances. The molecular weight of dry air is approximately 29, while water vapor's is 18, contributing to the overall dynamics of sound in humid conditions. Therefore, rain's primary effect is on sound transmission rather than speed.
Ezio3.1415
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I was suddenly asked this question by a friend...

How a 'cats & dogs' rain would affect the velocity of sound through air?(as we know velocity of sound through water is five times than in air)

I just couldn't be sure how to answer it... The raindrops are really small but there's a lot of them there... How big the effect could be?
 
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Ezio3.1415 said:
I was suddenly asked this question by a friend...

How a 'cats & dogs' rain would affect the velocity of sound through air?(as we know velocity of sound through water is five times than in air)

I just couldn't be sure how to answer it... The raindrops are really small but there's a lot of them there... How big the effect could be?

I doubt it changes the velocity at all unless there's mist accompanying the rain. What it DOES change is the amount of sound that propagates over a given distance.
 
The speed of sound depends mainly on temperature, but also on the humidity of the air. The sensitivity of the speed to humidity is also temperature dependent, which is not surprising since the fraction of water vapor in the air at "100% humidity" is very different at 0°C and 100°C. There is a graph here: http://www.phy.mtu.edu/~suits/SpeedofSound.html

The basic cause is the change in average molecular weight of the air. The MW of dry air is about 29, but the MW of water vapor is only 18.

As phinds said, the liquid raindrops don't have much effect on the speed of sound, but they scatter and absorb the sound waves.
 
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