Take the speed of the electron in the first Bohr orbit of hydrogen as 2.19x10^6 m s^-1. Find its speed in the n=3 orbit, in units of 10^5 m s^-1 (two decimals).

JEE Main levelNumerical answerDifficulty 2 of 3as079

Take the speed of the electron in the first Bohr orbit of hydrogen as $2.19 \times 1 0^{6} m s^{- 1}$ . Find its speed in the $n = 3$ orbit, in units of $1 0^{5} m s^{- 1}$ (two decimals).

Numerical answer type, answer in 1e5 m/s, tolerance 0.02.

v_{n} = v_{1} Z / n

, so

v_{3} = 2.19 \times 1 0^{6} /3 = 7.30 \times 1 0^{5} m s^{- 1}

. The answer is 7.30.