What is $rms$ value? What is $v_{rms}$? Derive the equation of $v_{rms}$ in terms of pressure.

Vedclass pdf generator app on play store
Vedclass iOS app on app store
(N/A) The $rms$ (root mean square) value is defined as the square root of the mean of the squares of the values.
$v_{rms}$ is the square root of the mean of the squares of the speeds of gas molecules.
According to the kinetic theory of gases,the pressure $P$ of an ideal gas is given by:
$P = \frac{1}{3} \rho \langle v^2 \rangle$
where $\rho$ is the density of the gas and $\langle v^2 \rangle$ is the mean square speed.
Rearranging the equation for $\langle v^2 \rangle$:
$\langle v^2 \rangle = \frac{3P}{\rho}$
Since $v_{rms} = \sqrt{\langle v^2 \rangle}$,we substitute the expression for $\langle v^2 \rangle$:
$v_{rms} = \sqrt{\frac{3P}{\rho}}$

Explore More

Similar Questions

The rms speed of a gas molecule is $V$ at pressure $P$. If the pressure is increased by two times,then the rms speed of the gas molecule at the same temperature will be

The temperature at which the root mean square velocity of hydrogen molecules equals their escape velocity from the Earth is closest to: [Boltzmann constant $k_B = 1.38 \times 10^{-23} \, J/K$,Avogadro number $N_A = 6.02 \times 10^{23} \, mol^{-1}$,Molar mass of $H_2 = 2 \times 10^{-3} \, kg/mol$,Radius of Earth $R_e = 6.4 \times 10^6 \, m$,Gravitational acceleration $g = 10 \, m/s^2$]

$A$ gas is at a temperature of $0^{\circ}C$. To what temperature in $^{\circ}C$ must the gas be heated so that the $rms$ speed of its molecules becomes double?

Difficult
View Solution

The $r.m.s.$ velocity will be greater for

The Maxwell distribution function for different gases is shown in the figure. Which of the following is the correct matching?

Vedclass Products

For Students

Vedclass Test Series

Mock tests in real JEE/NEET style with performance analysis. 5-day free trial.

Start Free Trial
For Teachers

Exam Paper Generator

Generate Set A/B/C/D exam papers from 7.5L+ questions in 2 minutes. 3 chapters free.

Try Free
For Institutes

Online Exam Module

Live online exams with unlimited students, 360° analytics & white-label branding.

See Demo