Question

An electron of $H$-atom from an exited state returns to ground state in one or more steps shows emission of ten lines. How many of these belongs to visible spectrum?

• A. $6$
• B. $5$
• C. $4$
• D. $3$

Answer 1

The correct option is D $3$

As we know,
$n(n-1)/2=10$ (given)
$\to n=5$
so no of lines emits in balmer series is (visible)
$n-2=5-2=3$