English
Tamil Nadu Board of Secondary EducationHSC Science Class 11

Write the expression for rms speed, average speed and most probable speed of a gas molecule. - Physics

Advertisements
Advertisements

Question

Write the expression for rms speed, average speed and most probable speed of a gas molecule.

Answer in Brief
Advertisements

Solution

Root mean square speed: (vrms)

vrms = `sqrtbar("v"^2) = sqrt(3"kT")/"m" = 1.73 sqrt("kT"/"m")`

Average speed: `(bar"v")`

`bar"v" = ("V"_1 + "v"_2 + "v"_3 + .... + "v"_"n")/"N"`

`bar"v" = sqrt((8"RT")/(π"M")) = sqrt((8"kT")/(π"m")) = 1.60 sqrt("kT"/"m")`

Most probable speed: (vmp)

vmp = `sqrt((2"RT")/"M") = sqrt((2"kT")/"m") = 1.41sqrt("kT"/"m")`

shaalaa.com
Root Mean Square (RMS) Speed
  Is there an error in this question or solution?
Chapter 9: Kinetic Theory of Gases - Evaluation [Page 185]

APPEARS IN

Samacheer Kalvi Physics - Volume 1 and 2 [English] Class 11 TN Board
Chapter 9 Kinetic Theory of Gases
Evaluation | Q II. 4. | Page 185

RELATED QUESTIONS

The velocity of the three molecules is 2 km s-1, 4 km s-1, 6 km s-1. Find (i) mean square velocity (ii) root mean square velocity. 


A fresh air is composed of nitrogen N2 (78%) and oxygen O2 (21%). Find the rms speed of N2 and O2 at 20°C.


If the rms speed of methane gas in the Jupiter’s atmosphere is 471.8 ms−1, shows that the surface temperature of Jupiter is sub-zero.


The molecular weights of oxygen and hydrogen are 32 and 2 respectively. The root mean square velocities of oxygen and hydrogen at N.T.P. are in the ratio ______


To what temperature should hydrogen at 227° C be cooled at constant pressure so that root mean square velocity of its molecule becomes half of its previous value?


A container has a mixture of two gases, hydrogen, and oxygen at room temperature. Which one of the following statements is true, if VH and VO are the root mean square velocities of hydrogen and oxygen molecules respectively?


The temperature at which the molecules of nitrogen will have the same r.m.s. velocity as the molecules of oxygen at 327° C is ____________.


The root mean square speed of the molecules of a gas is proportional to ______.
[T =Absolute temperature of gas]


What will be the effect on the root mean square velocity of oxygen molecules if the temperature is doubled and the oxygen molecule dissociates into atomic oxygen?


Compare the rms speed of hydrogen molecules at 227°C with the rms speed of oxygen molecules at 127°C. Given that molecular masses of hydrogen and oxygen are 2 and 32 respectively.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×