12. In a photoelectric experiment, a student obtained the following data: TT Frequency of Radiation (x10 Hz) Maximum Kinetic Energy (x 10 19 J) 6.2 5.3 4.2 3.5 1.9 2.56 2.00 1.31 0.90 0.45 a) Draw a graph that shows the relationship between the frequency of the incident radiation and the maximum kinetic energy of the electrons emitted from the photoelectric surface. Energy as a function of frequency: 3 350- 3.0- 250 1.50 I.00 రి,ఫం LO 20 30 40 5.0 60 7.0 Frequency (xlo“He) b) Using your graph, determine the threshold frequency and Planck's Constant. Planck's ConStanTt Slope =rise %3D run Energy (x10-195)

21 Green light shining on a sodium surface causes photoelectrons with maximum kinetic energies of 0.22 eV to be emitted. If the work function of sodium is 2.28 eV, what is the frequency of light used? 1ev= 1.6x10^-19J h= 6.673x10 ^-34 J s * L 5.2 x10^14 Hz 4.2 x10^14 Hz 6.0 x10^14 Hz 3.2 x10^14 Hz

0.2 eV 0.9 eV 1.1 eV A metal with a work function of 3.5 electron volts is exposed to photons of energy 3.7 electron volts. What is the maximum kinetic energy of the emitted photoelectrons? 7.7 eV

9. Considering the photoelectric effect; a) If a material has a cutoff wavelength of 780 nm what is the work function of the material? b) What is the maximum speed of liberated electrons when light with a wavelength of 410 nm is used to illuminate the material? c) If a liberated electron has 3.2349 eV of kinetic energy and it was a photon emitted from a hydrogen atom transition that liberated it, what energy level transition occurred? State both the initial and final energy level.

6. Given that the work function for a certain metal surface is 2.3 eV, find the stopping potential for photoelectrons ejected using incident light frequency of 7.0x1014 Hz. A. 0.9 volts B. 0.8 volts C. 0.3 volts D. 0.6 volts

You set up a photoelectric experiment with an unknown metal to eject electrons. You use light of wavelength λ = 660 nm, which just BARELY ejects electrons from the metal. Planck s constant is either h = 6.63 x 10-34 J.s or h = 4.14 x 10-15 ev.s. a) What is the binding energy of the unknown metal in eV? eV b) You change the light source to one with a wavelength of λ = 300 nm. Using the binding energy you found in the previous step, find the maximum kinetic energy of an electron that is ejected from the metal in Joules. c) What is the stopping voltage for an electron with the kinetic energy you just found? Submit Answer