Dual Nature Of Radiation And Matter Ques 70
70. The cathode of a photoelectric cell is changed such that the work function changes from $W_1$ to $W_2(W_2>W_1)$. If the current before and after changes are $I_1$ and $I_2$, all other conditions remaining unchanged, then (assuming $h v>W_2$ )
[1992]
(a) $I_1=I_2$
(b) $I_1<I_2$
(c) $I_1>I_2$
(d) $I_1<I_2<2 I_1$
Show Answer
Answer:
Correct Answer: 70.(a)
Solution:
- (a) The work function has no effect on photoelectric current so long as $h \nu>W_0$. The photoelectric current is proportional to the intensity of incident light. Since there is no change in the intensity of light, hence $I_1=I_2$.
BETA
