256 nm light strikes a metal and the ejected electrons have a stopping potential of 1.15 V. What is the work function of the metal in eV? (2) E = hf =

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256 nm light strikes a metal and the ejected electrons have a stopping potential of 1.15 V. What is the work function of the metal in eV? (2) E = hf = hc/, 1 eV = 1.602 x 10-19 J Photon energy = Work function + Kinetic energy of electron E = hf = hc/ = (6.626 x 10-34 Js)(3.00 x 108 m/s)/(256 x 10-9 m) E = 7.7648 x 10-19 J E = (7.7648 x 10-19 J)/(1.602 x 10-19 J/eV) = 4.847 eV Photon energy = Work function + Kinetic energy of electron 4.847 eV = Work function + 1.15 eV 11.079 eV - 1.15 eV = 3.70 eV W 3.70 eV

Light Wave model Photon model Color is Brightness is

Max. Energy of Ejected Electrons Wave model Photon model Depends on: Is independent of:

Find the equation of this line. What does the slope mean Find the equation of this line. What does the slope mean? What does the y-intercept mean? What kind of data is it?