Physics-
General
Easy
Question
The energy level diagram for an hydrogen like atom is shown in the figure. The radius of its first Bohr orbit is
- 0.265 Å
- 0.53 Å
- 0.132 Å
- None of these
The correct answer is: 0.265 Å
We know that 
and 
Here for n =1, E1 = – 54.4 eV
Therefore 
Þ Z = 2
Hence radius of first Bohr orbit 
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