Physics-
General
Easy
Question
An electron in Bohr’s hydrogen atom has an energy of –3.4 eV. The angular momentum of the electron is
- h/
- h/2
- nh/2 ( n is an integer)
- 2h/
( n is an integer)
The correct answer is: h/
The energy of an electron in an orbit of principal quantum number n is given as
E = 
Þ-3.4 eV = 
Þn2 = 4Þn = 2
The angular momentum of an electron in nth orbit is given as
L = 
, Putting n = 2
We obtain L = 
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