Bohr.s theory explains that when Hydrogen-like particles are excited, their electrons are shifted higher energy orbits. As such a state of atom is not stable, electrons return to lower energy orbits releasing quantum of energy. Thus different spectral lines are formed. The wave number of spectral line is given by `bar(v) = (2pi^(2)me^(4)z^(2))/(c h^(3))[(1)/(n_(1)^(2)-(1)/(n_(2)^(2)))]`
The angular momentum of an electron in a Bohr.s orbit of H-atom is `4.2178 xx 10^(-34) kg m^(2) sec^(-1)`. What is the wave number of the spectral line emitted when electron falls from this level to the next lower level

Options

A. `(7R)/(144)`
B. `5.5 xx 10^(-4) cm^(-1)`
C. `(8)/(9)R`
D. `1.1 xx 10^(-5)cm^(-1)`

Answer

A