Question

The frequency of emission line for any transition in positronium atom (consisting of a positron and an electron) is $x$ times the frequency for the corresponding line in the case of $H$ atom, where $x$ is

• A. $\sqrt{2}$
• B. $1 / 2 \sqrt{2}$
• C. $2 \sqrt{2}$
• D. $1 / 2$

Answer 1

Answer: (D)

Rydberg's constant determines the frequencies. We have $R \propto m$.
So, modified $R$ for positronium atom is half of $H$ atom.
Hence, frequencies are reduced to half.