Question

The average speed of an ideal gas molecule at $27{}^{\circ }C$ is $0.30\text{m/s}$. The average speed at $927{}^{\circ }C$ will be:-

• A. $1.2\text{m/s}$
• B. $0.60\text{m/s}$
• C. $0.15\text{m/s}$
• D. $1.8\text{m/s}$

Answer 1

The correct option is B $0.60\text{m/s}$

We know
$u_{av}\propto \sqrt{T}$ (temperature is measured in kelvin)
$\Rightarrow \frac{u_2}{u_1}=\sqrt{\frac{T_2}{T_1}}$
$\Rightarrow \frac{u_2}{0.30}=\sqrt{\frac{1200}{300}}\Rightarrow u_2=0.60\text{m/s}$