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I'm a little bit confused regarding the speed of sound in a gas. There are the following two equations:
1) v_gas = (γRT/molar mass)^1/2
2) v_gas = (γP/density)^1/2
I am reading some sources that say speed of sound is slower in denser objects of the same state (solid, liquid, gas) because it's harder to move them from their state of inertia. This would make sense with equation 2.
However, there's a question which asks "Which of the following reasons could NOT explain why an echo on the right side returns before an echo on the left side?"
a. The barrier on the left off which the sound echoes is farther away than the barrier on the right side.
b. The air on the left side is less dense than the air on the right side.
c. The air on the right side absorbs the sound.
d. The air on the left side is rich in a gas heavier than air.
Or would it be better to ignore the equations and go with the rule that denser mediums propagate waves faster, but HEAVIER molecules propagate waves slower due to their greater mass and thus smaller velocity (conservation of momentum)?
1) v_gas = (γRT/molar mass)^1/2
2) v_gas = (γP/density)^1/2
I am reading some sources that say speed of sound is slower in denser objects of the same state (solid, liquid, gas) because it's harder to move them from their state of inertia. This would make sense with equation 2.
However, there's a question which asks "Which of the following reasons could NOT explain why an echo on the right side returns before an echo on the left side?"
a. The barrier on the left off which the sound echoes is farther away than the barrier on the right side.
b. The air on the left side is less dense than the air on the right side.
c. The air on the right side absorbs the sound.
d. The air on the left side is rich in a gas heavier than air.
So C is obviously best answer, but I thought B would also be correct, given that the less dense air on the left side would lead to v_gas being greater, given equation 2? I understand the answer theoretically: a less dense medium would be less able to propagate the sound waves since the molecules are farther apart, therefore the left side echo would take longer. However, doesn't this contradict equation 2? Or would it be better to ignore the equations and go with the rule that denser mediums propagate waves faster, but HEAVIER molecules propagate waves slower due to their greater mass and thus smaller velocity (conservation of momentum)?
