Equating two formulas for root-mean-square velocity

In summary, the root-mean-square velocity is calculated by taking the square root of the average of the squared velocities of particles in a system. It differs from average velocity because it considers the magnitude of individual velocities, making it a more accurate representation of overall speed. Equating two formulas for RMS allows for a better understanding and comparison of particle behavior. RMS can be used for all types of particles and is directly proportional to the square root of temperature according to the kinetic theory of gases.
  • #1
JC2000
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Homework Statement
Compare ##v_{rms}##, ##v_{most probable}## and ##v_{average}## (arrange them in increasing/decreasing order).
Relevant Equations
##v_{rms} = \sqrt {\frac{3RT}{M}}## where ##M## is molar mass of the gas. ... (1)
##v_{rms} = \sqrt {\frac{3k_{B}T}{m}}## where ##m## is the molecular mass of the gas. ...(2)
## N_A*k_B = n*R## where ##N_A## is Avogadro's number and ##n## is the number of moles of the gas.
## \frac{M}{N_A} = m## (?)
(a)
My question :
Are all the formulas correct?

If so I can write ##v_{rms}## in form (2) and compare that result with the other velocities to get the answer (rms > average > most probable)
 
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  • #2
If by "molecular mass" you mean the mass of one molecule, then all of the above is correct.
 
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  • #3
kuruman said:
If by "molecular mass" you mean the mass of one molecule, then all of the above is correct.

Yes, thanks for going through it all!
 

What is the concept of root-mean-square velocity?

Root-mean-square velocity is a mathematical concept used to describe the average velocity of particles in a system. It takes into account the magnitude and direction of individual velocities, resulting in a single value that represents the average velocity of all particles.

Why is it important to equate two formulas for root-mean-square velocity?

Equate two formulas for root-mean-square velocity is important because it allows for a more accurate calculation of the average velocity of particles. It ensures that all relevant factors are taken into account and eliminates any discrepancies between the two equations.

What are the two commonly used formulas for calculating root-mean-square velocity?

The two commonly used formulas for calculating root-mean-square velocity are the Maxwell-Boltzmann distribution formula and the kinetic theory formula. Both of these equations take into account the mass, temperature, and speed of particles in a system.

What are the key differences between the two formulas for root-mean-square velocity?

The key differences between the two formulas for root-mean-square velocity lie in the assumptions and factors they take into account. The Maxwell-Boltzmann distribution formula assumes a gas of particles with different speeds, while the kinetic theory formula assumes a gas of particles with the same speed. Additionally, the Maxwell-Boltzmann formula includes a constant (k) to account for different types of particles, while the kinetic theory formula does not.

How can equating two formulas for root-mean-square velocity be applied in real-world situations?

Equate two formulas for root-mean-square velocity can be applied in various fields such as physics, chemistry, and engineering to calculate the average velocity of particles in a system. It can also be used to understand and analyze the behavior of gases and particles in different conditions, such as temperature and pressure changes. In industries, this concept is used to optimize processes and improve efficiency.

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