Need to know what the K stands for in this equation

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SUMMARY

The discussion confirms that in the equation for Root Mean Squared (RMS) speed, the constant 'k' represents the Boltzmann constant, valued at 1.4e-23. This equation is specifically applicable to the RMS speed of a molecular gas at temperature T, measured in Kelvin, with molecular mass m in kilograms. Participants emphasized the importance of ensuring that calculations are performed using the correct temperature scale and proper parentheses in the equation to avoid errors.

PREREQUISITES
  • Understanding of the Root Mean Squared speed calculation
  • Knowledge of the Boltzmann constant (1.4e-23)
  • Familiarity with temperature scales, specifically Kelvin
  • Basic algebraic skills for manipulating equations
NEXT STEPS
  • Research the derivation of the Root Mean Squared speed formula
  • Study the properties and applications of the Boltzmann constant
  • Learn about temperature conversions and absolute temperature scales
  • Explore common pitfalls in scientific calculations, particularly with square roots
USEFUL FOR

Students and professionals in physics, particularly those studying thermodynamics or kinetic theory, as well as anyone involved in calculations related to molecular gas behavior.

LocalStudent
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I'm busy solving a physics question and I am getting unexpected results.

I just want to check if I am using the right constant in this equation:
I am using the equation to find the Root Mean Squared speed = √(8/3∏) √3kT/m

Is k in this equation the Boltzmann constant? (1.4e-23)
 
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Yes it is. (As long as you are indeed talking about the RMS speed of a molecular gas or some such at temperature T with molecular mass m)
 
Matterwave said:
Yes it is. (As long as you are indeed talking about the RMS speed of a molecular gas or some such at temperature T with molecular mass m)

Thanks. Then I must be going wrong somewhere else.. I'm sure I'll find it. Thanks again
 
T is in Kelvin, is that the temperature scale you have used?
 
Make sure your temperature is in absolute scale (e.g. Kelvin), not degrees.
 
I've used kelvin. And mass in kilograms.

Thanks for the input. I'll post the actual question later and you could see if I've done it correctly or not.
 
Have you been careful and told your calculator what the correct radicands are? That is, have you used parantheses around the full expression that should stand under the square root signs?
 

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