Question

The velocity of the molecules of a gas at temperature 120 K is v. At what temperature will the velocity be 2v?

• A. 120 K
• B. 240 K
• C. 480 K
• D. 1120 K

Answer 1

The correct option is C 480 K

$V$ $\propto$ $\sqrt{T}$
$\therefore \frac{V^{\prime }}{V}$ =$\sqrt{\frac{T^{\prime }}{T}}$
Given $V^{\prime }$ = 2V
or $\frac{2}{1}=\sqrt{\frac{T^{\prime }}{T}}$
$\therefore T^{\prime }$ = $4T$ = $4\times 120K$
$=480K$