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Question
The work function of a metal is 4.50 eV. Find the frequency of light to be used to eject electrons from the metal surface with a maximum kinetic energy of 6.06 × 10−19 J.
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Solution
Maximum kinetic energy of photoelectron = Energy of incident photon − Work function
Or, 6.06 × 10−19 = hv − 4.5 × 1.6 × 10−19
Or, hv = 13.26 × 10−19
Or, v = `((13.26 xx 10^-19))/((6.6 xx 10^-34))`
∴ v = 2 × 1015 Hz
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