Question:medium

If \( \lambda \) is the incident wavelength and \( \lambda_0 \) is the threshold wavelength for a metal surface, photoelectric effect takes place only if:

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Shorter wavelength (higher frequency) is needed for photoelectric emission.

Updated On: Apr 16, 2026

\( \lambda \le \lambda_0 \)
\( \lambda \ge \lambda_0 \)
\( \lambda \ge 2\lambda_0 \)
None of these

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The Correct Option is A

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