JEE PYQ: Atomic Physics Question 63
Question 63 - 2019 (12 Jan Shift 1)
When a certain photosensitive surface is illuminated with monochromatic light of frequency $\nu$, the stopping potential for the photo current is $-V_0/2$. When the surface is illuminated by monochromatic light of frequency $\nu/2$, the stopping potential is $-V_0$. The threshold frequency for photoelectric emission is:
(1) $\frac{5\nu}{3}$
(2) $\frac{4}{3}\nu$
(3) $2\nu$
(4) None of the above
Show Answer
Answer: (4)
Solution
$h\nu = \phi + eV_0/2$ …(i). $h\nu/2 = \phi + eV_0$ …(ii). From these equations the threshold frequency can be determined. The answer is option (4).
BETA
