Single Choice

Light of frequency $$1.5$$ times the threshold frequency is incident on a photosensitive material. What will be the photoelectric current if the frequency is halved and intensity is doubled?

Afour times
Bone-fourth
Czero
Correct Answer
Ddoubled

Solution

The photoelectric current is obtained beyond the threshold frequency.
If the frequency of the light is halved, then it will become $$f'=\dfrac{1.5}{2}=0.75$$ times the threshold frequency.

Since this is less than the threshold frequency, there will be no photoelectric current.

SIMILAR QUESTIONS

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