Dual Nature Of Light Question 257
Question: A photo cell is receiving light from a source placed at a distance of 1 m. If the same source is to be placed at a distance of 2 m, then the ejected electron [MNR 1986; UPSEAT 2000, 01]
Options:
A) Moves with one-fourth energy as that of the initial energy
B) Moves with one-fourth of momentum as that of the initial momentum
C) Will be half in number
D) Will be one-fourth in number
Show Answer
Answer:
Correct Answer: D
Solution:
Number of ejected electrons $ \propto \text{(Intensity)}\propto \frac{1}{{{(Distance)}^{2}}} $ Therefore an increment of distance two times will reduce the number of ejected electrons to $ \frac{1}{4}th $ of the previous one.
BETA
