Ratio of frequency of revolution of electron in the second excited state of He⊕ and second state of hydrogen is
Step 1:
Frequency v=V2πr; V∝Zn and r∝n2Z
V=Z×Zn×n
Step 2:
⇒v∝z2n3
So vHe⊕2vH⊕2=22321222=8×427=3227
Hence, option (A) is correct.
Second excited ⇒ n=3