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Photoelectric effect experiments are per...

Photoelectric effect experiments are performed using three different metal plates `p,q` and`r` having work function `phi_(p) = 2.0 eV, phi_(e) = 2.5 eV and phi_(r) = 3.0 eV` respectively A light beam containing wavelength of `550nm , 450 nm` and `350nm ` with equal intensities illuminates each of the plates . The correct `I -V` graph for the experiment is [Take hc = 1240 eV nm]

A

B

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D

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The correct Answer is:
A
550 nm light cannot emit electron for metal of work function `phi=3eV`, so saturate current decreases for P to Q to R. Also `|V_(sp)| gt |V_(sq)| gt |V_(sr)|`
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ALLEN -SIMPLE HARMONIC MOTION-Exercise-05(B)
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