Question:
When a certain photosensistive surface is illuminated with monochromatic light of frequency $v$, the stopping potential for the photo current is $-\mathrm{V}_{0} / 2$. When the surface is illuminated by monochromatic light of frequency $v / 2$, the stoppoing potential is $-\mathrm{V}_{0}$. The threshold frequency for photoelectric emission is :
Correct Option: , 4
Solution:
(4)