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In the photoelectric effect, a beam of light with frequency n1 produces a stopping potential V1. If this light is replaced by another beam of frequency n2, what will be the new stopping potential?

1. V1 - (h/e)(n2 - n1)
2. V1 + (h/e)(n2 + n1)
3. V1 + (h/e)(n2 - 2n1)
4. V1 + (h/e)(n2 - n1)

Correct answer: V1 + (h/e)(n2 - n1)

Solution

The stopping potential is directly related to the energy of the incident photons, which is determined by their frequency. When the frequency changes from n1 to n2, the change in energy corresponds to the difference in stopping potential, leading to the formula V1 + (h/e)(n2 - n1) for the new stopping potential.

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