WBJEE · Physics · Dual Nature of Matter
A point source of light is used in an experiment of photo-electric effects. If the distance between the source and the photo-electric surface is doubled, which of the following may result?
- A Stopping potential will be halved
- B photo-electric current will decrease
- C Maximum kinetic energy if photo-electrons will decrease
- D Stopping potential will increase slightly
Answer & Solution
Correct Answer
(B) photo-electric current will decrease
Step-by-step Solution
Detailed explanation
Hint: Intensity \(\mathrm{I} \propto \frac{1}{\text { d }}\) and photo-electric current \(\propto\) intensity \(\therefore\) Current will decrease
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