There are two types of waves transverse waves and mechanical waves. And the sound wave falls into the second category, the mechanical wave.
The sound waves travel through a medium by oscillating the matter in that medium. It is incapable of traveling through a vacuum as it requires a medium.
Now onto a more real-life explanation of how the sound wave travels through a medium. When an object produces a sound, the medium near it oscillates, and that oscillation is transferred to the nearest molecule of the medium.
It continues further, although we can only experience the much more condensed oscillation.
v = √ (γRT)/M
γ = Adiabatic constant
R = Gas constant
T = Absolute temperature
M = Molecular mass of the medium (here, the mass of the air/gas)
v = 331.29 meters per second. (Standard atmospheric temperature and pressure)
We may believe that this is the speed of sound in all cases, but other external factors affect the speed of sound like temperature, density, the elasticity of the medium, etc.
The three factors that affect the sound wave are frequency, the elasticity of the medium, and temperature. The frequency of the sound wave affects its loudness and pitch.
The nature of the medium also affects the sound wave. The denser the medium is, the slower the sound travels. The temperature is directly proportional to the speed of the sound wave. The higher the temperature is, the faster the sound wave travels.
Medium* | Speed** |
Aluminum | 6320 |
Glass | 4540 |
Water | 1437 |
Dry air | 343 |
*At standard temperature that is 20 C
**In meters per second
Does Sound Travel Faster in Cold Air or Warm Air?
You must have experienced when you are staying near the road, and then a loud vehicle passed, and it was so loud for you, but the driver or the passenger, it was not that loud. You might have wondered why. It has got a connection with atmospheric temperature. The explanation will be given in the course of reading
The sound travels faster in warm air than in cold air because the particles in the warm air oscillate much more rapidly than the particles in the cold air. And as a result, the sound wave travels faster in warm air. Sometimes it may move so fast that we could not almost hear it. The frequency also takes half of the credit off us not being able to hear it.
Why Does Sound Travel Faster in Warm Air?
As said above, particles oscillate more rapidly in the warm air, which is why sound travels much faster in warm air. But why do the particles travel much faster in warm air? As we all know, heat is a form of kinetic energy, or rather the kinetic energy of the particles changes into the heat energy. Either way, we conclude that the warm air consists of more kinetic energy than the cold air.
You must have experienced the sound of the traffic is much louder a bit far away from the traffic rather than in the traffic. This is due to the air being hotter a bit above the ground. Hence the sound travels up in the air and gets refracted to the surface, and ends up a bit far away due to the angle. To conclude, sound travels faster in the warm air than in the cold air due to the kinetic energy of the particles of the medium.
We should not neglect the nature of the medium per the temperature. The density of the medium and the temperature are inversely proportional, which means as the temperature increases, the density of the medium decreases.
Does Sound Travel Farther in Cold Air?
Yes, the sound travels farther in the cold air. Why? Because the density of the cold air is more. You can hear the sound more loudly and from a distant location on a rainy day than on a sunny day.
This is due to the temperature becoming lower and, as a result, the humidity increasing (which may result in an increase in atmospheric temperature due to the refraction of the heatwave in the particles); hence the sound wave can refract /echo a lot and thus becoming louder which gives way to an increased frequency and the sound traveling faster.
Why Does Sound Travel Farther in Cold Air?
Because the cold air is a much denser medium than the warm air, and as a result, the sound can travel further as there are more particles to oscillate and thus carry out the sound to a farther distance before it loses its frequency.
While the warm air has lesser particles to oscillate and thus it loses its frequency much faster and loses its loudness to a level that we cannot hear. And also, because the sound refracts more in cold air and more refractions happen, it becomes louder.
While the sound travels faster in the warm air, it travels farther in the cold air.
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Final Thoughts
Here we have discussed how the temperature affects the speed of sound.
To conclude, does the sound travel faster in warm air? Yes, the sound does travel more quickly in warm air. Now on to the next question, why does the sound travel faster in the warm air? Because the molecule’s kinetic energy is higher in warm air than in cold air. As a result, the molecules vibrate rapidly and end up traveling faster.
Does the sound travel farther in cold air? Yes, the sound does travel farther in cold air. Why does the sound travel farther in cold air? Because the cold air is denser than the warm air, the sound gets refracted more and gets louder and hence gets a higher frequency and travels farther than it dies in the warm air. The sound travels faster in warm air but further in cold air.