Incident radiation energy is increased by 20% and maximum kinetic energy rises from 0.5 eV to 0.8 eV. Find the metal work function.
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Incident radiation energy is increased by 20% and maximum kinetic energy rises from 0.5 eV to 0.8 eV. Find the metal work function.

G1 Physics · Accepted Answer

Let incident photon energy be E and work function W. E − W = 0.5 and 1.2E − W = 0.8. Subtract: 0.2E = 0.3 ⇒ E = 1.5 eV. Then W = E − 0.5 = 1.0 eV. Answer: B.