Q. An electron, $e_{1}$ is moving in the fifth stationary state, and another electron $e_{2}$ is moving in the fourth stationary state. The radius of orbit of electron, $e_{1}$ is five times the radius of orbit of electron, $e_{2}$ calculate the ratio of velocity of electron $e_{1}\left(v_{1}\right)$ to the velocity of electron $e_{2}\left(v_{2}\right)$.
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