The wavelength of the first spectral line in the Balmer series of the hydrogen atom is

PHYSICS · Single correct · CBSE · Physics · Atoms · Atoms

Problem

6561\,\text{\AA}

. The wavelength of the second spectral line in the Balmer series of singly ionized helium is (1)

1215\,\text{\AA}

(2)

1640\,\text{\AA}

(3)

2430\,\text{\AA}

(4)

4687\,\text{\AA}