- #1
Sara077
- 4
- 0
Homework Statement
Light illuminates a metallic surface with work function of 1.20 eV. It takes 1.0 V of retarding potential to stop all of the photoelectrons from reaching the opposite plate. Find the maximum speed of the photoelectrons.
Homework Equations
hf = w
hf = w + Ek
The Attempt at a Solution
First work function = 1.20eV(1.60x10-19 J/eV) = 1.92x10-19 J
Not really sure how to do this problem... but giving it a go here:
First,
hf = w
f = w/h
f = 1.92x10-19 J / 6.63x10-34 Js
f = 2.9x1014 Hz
Now i got the frequency, i assume i use:
hf = w+ Ek
Ek = hf - w
1/2mv2 = hf - w
Is this correct so far? If yes do i just plug in the numbers and solve for "v" also not really sure what to do with the retarding potential?