No idea how to do either of these... 1) When light of wavelength 259 nm shines o
ID: 2299694 • Letter: N
Question
No idea how to do either of these...
1) When light of wavelength 259 nm shines on a metal surface the maximum kinetic energy of the photoelectrons is 1.99 eV. What is the maximum wavelength (in nm) of light that will produce photoelectrons from this surface?
and
2) The following data gives stopping potential V0 versus wavelength for photoelectrons produced from a metal surface. (Be sure to include the correct units and use three significant figures.)
Table 1
Use an analysis similar to that used in the inlab procedure to determine the work function (in eV) for this surface.
?(nm) V0
(volts) 50 22.1 100 9.27 150 5.19 200 3.11 250 1.86 300 1.05
Explanation / Answer
E = Wo + KE
==> Wo = E - KE
= h*c/lamda - KE
= 6.634*10^-34*3*10^8/259*10^-9 - 1.99 eV
= 7.684*10^-19 - 1.99 eV
= 4.8 eV - 1.99 eV
= 2.81 e V
Wo = h*c/lamdao
==> lamdao = h*c/Wo
= 6.634*10^-34*3*10^8/(2.81*1.6*10^-19)
= 442.6 nm <<<<<<<-Answer