Kinetic theory of gases - can someone check this please?

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SUMMARY

The discussion centers on the relationship between pressure and root mean square (rms) speed in the context of the kinetic theory of gases. The equation derived is rms speed = √(3p/ρ), indicating that if pressure (p) is halved while keeping temperature constant, the rms speed becomes rms speed = (9/4)√(p/ρ). This shows that the rms speed does not get quartered but rather is reduced to 75% of its original value. The relationship between temperature and molecular speed is also questioned, highlighting the need for further exploration of this concept.

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QueenFisher
i'm given that p= [tex]\frac{1}{3}\rho\overline{c^2}[/tex]

without calculation, what happens to rms speed if pressure halved, temperature constant?

firstly, just from rearranging the original equation, you get

[tex]\overline{c^2}[/tex] = [tex]\frac{3p}{\rho}[/tex]

square rooting both sides to get rms speed gives:

rms speed = [tex]\sqrt{\frac{3p}{\rho}}[/tex]

which rearranges to rms speed = 9 [tex]\sqrt{\frac{p}{\rho}}[/tex]

then, using original equation, when pressure halved, you get:

[tex]\overline{c^2}[/tex] = [tex]\frac{3p}{2\rho}[/tex]

square rooting both sides to get rms speed gives:

rms speed = [tex]\sqrt{\frac{3p}{2\rho}}[/tex]

which rearranges to rms speed = [tex]\frac{9}{4}[/tex] [tex]\sqrt{\frac{p}{\rho}}[/tex]

so is it ok to say that the rms speed is quartered?
 
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