alleryIf the absolute temperature of an ideal gas is doubled, the rms speed of its molecules:
ADoubles
BIncreases by a factor of $\sqrt{2}$
CQuadruples
DHalves
Answer & Solution
Correct answer: B. Increases by a factor of $\sqrt{2}$
$v_{\text{rms}} \propto \sqrt{T}$ (in Kelvin). Doubling $T$ scales the rms speed by $\sqrt{2}$.
Intuition: kinetic energy is proportional to $T$, and KE $\propto v^2$, so $v \propto \sqrt{T}$.
Option A (doubles) would be true if $v \propto T$, but it's $\sqrt{T}$.
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