Bio-Physics (M.Phil./Ph.D.) 2018 Panjab University Entrance Exam With Answers

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7.

In the helium-neon laser, which of the following is not true?

A: The laser transition occurs in helium atom
B: The purpose of the helium atom is to help achieve a population inversion in the neon atoms
C: There is stimulated emission as well as spontaneous emission in the Neon atoms
D: The metastable state occur in both the Helium and Neon atoms.

The answer is: A