The work function of sodium metal is \(4.41 \times 10^{-19}\) J. If photons of wavelength 300 nm are incident on the metal, the kinetic energy of the ejected electrons will be (h = \(6.63 \times 10^{-34}\) J s; c = \(3 \times 10^{8}\) m/s) ________ \(\times 10^{-21}\) J.
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Correct Answer: 222
Solution and Explanation
KE = E - φ = 6.63 × 10-19 - 4.41 × 10-19 = 2.22 × 10-19 J = 222 × 10-21 J.
Answer: 222
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