Question

Number of spectral lines of Lyman series of electron when it jumps from $6$ to first level (in Lyman series), is

• A. 9
• B. 12
• C. 15
• D. 18

Answer 1

Answer: (C)

Number of spectral lines $=\frac{n(n-1)}{2}$
$=\frac{6(6-1)}{2}$
$=15$