A photocathode that has a work function of 2.4 eV is illuminated with monochromatic light having photon energy 3.5 eV.What is the wavelength of this light? (c = 3.00 × 10⁸ m/s,h = 6.626 × 10^-34 J ∙ s,1 eV = 1.60 × 10^-19 J) A)350 nm B)330 nm C)300 nm D)380 nm E)410 nm

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The correct answer is A because the wavelength of the light can be calculated using the formula:λ = hc / Ewhere:λ is the wavelength in metersh is Planck's constant (6.626 × 10^-34 J ∙ s)c is the speed of light (3.00 × 10^8 m/s)E is the energy of the photon in joulesIn this case, the energy of the photon is:E = 3.5 eV * 1.60 × 10^-19 J / eV = 5.60 × 10^-19 JSubstituting these values into the formula, we get:λ = (6.626 × 10^-34 J ∙ s * 3.00 × 10^8 m/s) / (5.60 × 10^-19 J) = 350 nm

A Photocathode That Has a Work Function of 2