When the light of frequency $2 v_0$ (where $v_0$ is the threshold frequency) is incident on a photosensitive material, the maximum velocity of electrons emitted is $v_1$. When the frequency of the incident raditation is increased to $3 v_{0}$, the maximum velocity of emitted electrons from the same material is $v_2$. The ratio of $v_1$ to $v_2$ will then be:

$1: \sqrt{2}$

The correct answer is Option (4) → $1: \sqrt{2}$