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The cathode of a photoelectric cell is changed such that the work function changes from W₁ to W₂ (W₂ > W₁). If the current before and after changes are I₁ and I₂, all other conditions remaining unchanged, then (assuming hν > W₂):

1. I₁ = I₂
2. I₁ < I₂
3. I₁ > I₂
4. I₁ < I₂ < Z₁

Correct answer: I₁ = I₂

Solution

The photoelectric current depends on the intensity of incident light and not on the work function, provided the photon energy is greater than the work function. Since hν > W₂ and all other conditions remain unchanged, the current remains the same, i.e., I₁ = I₂.

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