Question

how many spectral lines are possible between n= 2 to n= 7?
Plz give me the full solution​
Science question

Answer 1

Formula for total Spectral lines for any transition:

∑(n₂−n₁) or (n₂−n₁)(n₂−n₁+1)/2

=> ∑(7−2) = ∑ (5) = 5+4+3+2+1 = 15