The temperature of an ideal gas is increased from 27°C to 927°C. The root mean square speed of its molecules becomes

 

1. Twice

 

2. Half

 

3. Four times

 

4.One-fourth

According to the kinetic theory of gases the r.m.s. velocity of gas molecules is directly proportional to

1. $\mathrm{T}$                                 

2. $\sqrt{\mathrm{T}}$

3. ${\mathrm{T}}^2$                                 

4. $1/\sqrt{\mathrm{T}}$

At a given temperature the root mean square velocities of oxygen and hydrogen molecules are in the ratio

1.  16 : 1                               

2.  1 : 16

3.  4 : 1                                 

4.  1 : 4

The value of densities of two diatomic gases at constant temperature and pressure are ${\mathrm{d}}_1$ and ${\mathrm{d}}_2 ,$ then the ratio of the speed of sound in these gases will be :

1. ${\mathrm{d}}_1{\mathrm{d}}_2$                                   

2. $\sqrt{{\mathrm{d}}_2/{\mathrm{d}}_1}$

3. $\sqrt{{\mathrm{d}}_1/{\mathrm{d}}_2}$                             

4. $\sqrt{{\mathrm{d}}_1{\mathrm{d}}_2}$

By what factor the r.m.s. velocity will change, if the temperature is raised from 27°C to 327°C

1.  $\sqrt{2}$                                 

2.  $2$

3.  $2\sqrt{2}$                               

4.  $1$

At a given temperature if ${\mathrm{V}}_{\mathrm{rms}}$ is the root mean square velocity of the molecules of a gas and ${\mathrm{V}}_{\mathrm{s}}$ the velocity of sound in it, then these are related as $\left(\mathrm{\gamma }=\frac{{\mathrm{C}}_{\mathrm{P}}}{{\mathrm{C}}_{\mathrm{v}}}\right)$

1. ${\mathrm{V}}_{\mathrm{rms}}={\mathrm{V}}_{\mathrm{s}}$                             

2. ${\mathrm{V}}_{\mathrm{rms}}=\sqrt{\frac{3}{\mathrm{\gamma }}}\times {\mathrm{V}}_{\mathrm{s}}$

3. ${\mathrm{V}}_{\mathrm{rms}}=\sqrt{\frac{\mathrm{\gamma }}{3}}\times {\mathrm{V}}_{\mathrm{s}}$                   

4. ${\mathrm{V}}_{\mathrm{rms}}=\left(\frac{3}{\mathrm{\gamma }}\right)\times {\mathrm{V}}_{\mathrm{s}}$

For a gas at a temperature the root-mean-square velocity ${\mathrm{v}}_{\mathrm{rms}}$ , the most probable speed ${\mathrm{v}}_{\mathrm{mp}}$ , and the average speed ${\mathrm{v}}_{\mathrm{av}}$ obey the relationship

1. ${\mathrm{v}}_{\mathrm{av}}>{\mathrm{v}}_{\mathrm{rms}}>{\mathrm{v}}_{\mathrm{mp}}$                               

2. ${\mathrm{v}}_{\mathrm{rms}}>{\mathrm{v}}_{\mathrm{av}}>{\mathrm{v}}_{\mathrm{mp}}$

3. ${\mathrm{v}}_{\mathrm{mp}}>{\mathrm{v}}_{\mathrm{av}}>{\mathrm{v}}_{\mathrm{rms}}$                               

4. ${\mathrm{v}}_{\mathrm{mp}}>{\mathrm{v}}_{\mathrm{rms}}>{\mathrm{v}}_{\mathrm{av}}$

The r.m.s. speed of a group of 7 gas molecules having speeds $\left(6, 4, 2, 0, -2, -4, -6\right) \mathrm{m}/\mathrm{s}$ is

1. $1.5 \mathrm{m}/\mathrm{s}$                                   

2. $3.4 \mathrm{m}/\mathrm{s}$

3. $9 \mathrm{m}/\mathrm{s}$                                       

4. $4 \mathrm{m}/\mathrm{s}$

If the ratio of vapour density for hydrogen and oxygen is $\frac{1}{16}$ , then under constant pressure the ratio of their rms velocities will be

1. $\frac{4}{1}$                                   

2. $\frac{1}{4}$

3. $\frac{1}{16}$                                 

4. $\frac{16}{1}$

Molecular motion shows itself as

1. Temperature                     

2. Internal Energy

3. Friction                             

4. Viscosity