When an electron in the hydrogen atom in ground state absorb a photon of energy `12.1eV`, its angular momentum

Options

A. decreases by `2.11 xx 10^(-34) Js`
B. decreases by `1.055 xx 10^(-34)Js`
C. Increases by `2.11 xx 10^(-34) Js`
D. increases by `1.055 xx 10^(-34)Js`.

Answer

C

Explanation

After absorbing a photon of energy 12.1 e V electron jumps from ground state (n=1) to second excited state (n=3). Therefore change in angular momentum `Delta L = L_(3) -L_(1) =3 ((h)/(2pi))-(h)/(2pi)=(h)/(pi)`
`=(6.6 xx10^(-34))/(3.14)Js =2.11 xx 10^(-34) Js`