MCQ
The photocurrent in an experiment on photoelectric effect increases if:
- AThe intensity of the source is increased.
- BThe exposure time is increased.
- CThe intensity of the source is decreased.
- DThe exposure time is decreased.
✓
Answer
- The intensity of the source is increased.
Explanation:
When the intensity of the source is increased, the number of photons emitted from the source increases. As a result, a large number of electrons of the metal interact with these photons and hence, the number of electrons emitted from the metal increases. Thus, the photocurrent in an experiment of photoelectric effect increases. The photocurrent does not depend on the exposure time.
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