Calculate the maximum kinetic energy of photoelectrons emitted from this plate when light of wavelength (λ) 520nm is directed at the metal surface.
work function (ф) of the plate = 1.1 × 10⁻¹⁹ j
planck's constant (h) = 6.63 × 10⁻³⁴ js
frequency (f) = c ÷ λ
c = speed light in vacuum = 3.00 × 10⁸ms⁻¹
ekmax = hf - φ
wavelength must be in metres, so it'll be 590×10⁻⁹
i've worked this out and gotten two different answers so i thought i'd check to see which one is right.

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