When a metal is illuminated by light,photoelectrons are observed provided that the wavelength of the light is less than 520 nm.What is the metal's work function? (c = 3.00 × 10⁸ m/s,h = 6.626 × 10^-34 J ∙ s,1 eV = 1.60 × 10^-19 J) A)2.4 eV B)2.6 eV C)2.8 eV D)3.0 eV

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Quizplus · Accepted Answer

The energy of a photon is given by E = hc/λ, where h is Planck's constant, c is the speed of light, and λ is the wavelength. The work function is the minimum energy required to remove an electron from a metal. If the energy of the photon is greater than or equal to the work function, then an electron will be emitted. In this case, the wavelength of the light is 520 nm, which corresponds to an energy of 2.4 eV. Therefore, the work function of the metal must be less than 2.4 eV. The only choice that is less than 2.4 eV is A, 2.4 eV.

When a Metal Is Illuminated by Light,photoelectrons Are Observed Provided