At source distance d, a photoelectric cell emits n photoelectrons per unit time. If distance is reduced to d/2, count becomes:
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At source distance d, a photoelectric cell emits n photoelectrons per unit time. If distance is reduced to d/2, count becomes:

G1 Physics · Accepted Answer

I ∝ 1/d² and the emission rate ∝ intensity. With new distance d/2, intensity is 4 times larger, hence emission count is 4n. Answer: C.