Ultraviolet light of wavelength 250 nm falls normally on a metal surface whose work…
PHYSICS · Multi-part · A Level · Physics · Particles and radiation · Particles and radiation
Problem
Ultraviolet light of wavelength 250 nm falls normally on a metal surface whose work function is 2.0 eV. The incident beam has a power of 1.0 mW and 5 % of the photons eject electrons.
(e = 1.6×10^{-19} C, h = 6.63×10^{-34} J s, c = 3.0×10^{8} m s^{-1}, 1 eV = 1.6×10^{-19} J)
(a) Calculate the energy of one incident photon.
(b) Find the maximum kinetic energy of the emitted electrons in eV.
(c) Determine the photocurrent produced if every emitted electron contributes to the current.