Physics-
General
Easy
Question
In an experiment of photo-electric effect, singly ionized ‘He’ is excited electronically to different energy levels. The emission spectra of the He hence produced is made incident on a photoelectric plate in the photo-cell. When He is excited to fourth energy level then the observed stopping potential of photo –cell is found to be five times the stopping potential when hydrogen is excited to third energy level. The work function of the material of the photo electric plate is
- 1.21 eV
- 1.76 eV
- 2.04 eV
- 2.36 eV
The correct answer is: 2.36 eV
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