PhotoElectric Effect Question

In summary, the maximum kinetic energy of the ejected electrons can be calculated using the equation KE = hc/wavelength - Wo, where Wo is the work function and hc is Planck's constant times the speed of light. By substituting the given values of wavelength and Wo, the maximum k.e. is found to be 1.2015*10^-19.
  • #1
Panic Attack
14
0

Homework Statement


What is the maximum energy of the ejected electrons? When the radiation wavelength is 100 nm, and the stopping potential of the metal is 8.


Homework Equations


KE = hc/wavelenght - Wo


The Attempt at a Solution


I found the work function and the cut off wavelength to be the following but I can't figure out the max energy...

KE = hc/wavelenght - Wo

Wo = work function = { (6.63 *10^-34)(3*10^8) / (100 *10^9) } - (1.6*10^-19)(8)
Fo = cut off frequency = Wo / (6.63 *10^-34)
 
Physics news on Phys.org
  • #2
I think I have an answer, but I don't know if it is right...

E = Wo + KE, where Wo = 1.225*10^-19, in which I solved for
E = hc/lambda = 6.62*10^-34 * 3*10^8 / 150*10^-19 = 1.324*10^-18

E = Wo + KE
1.324*10^-18 = 1.225*10^-19 + KE

KE = 1.2015*10^-19?

Can someone tell me if this is right?
 
  • #3
If it is not too late...

The max k.e. should be 8 eV
 
  • #4
john54 said:
If it is not too late...

The max k.e. should be 8 eV

It's never too late. I think I got this problem wrong then. Can you explain how you got 8?
 
  • #5
Panic Attack said:
KE = hc/wavelenght - Wo
You are given wavelength and Wo in the problem statement, and are asked to calculate KE. You seem to be over-complicating things. (The answer is not 8 eV, by the way.)
 
  • #6
Redbelly98 said:
You are given wavelength and Wo in the problem statement, and are asked to calculate KE. You seem to be over-complicating things. (The answer is not 8 eV, by the way.)

teheheh... I got it right den... :)
 

1. What is the PhotoElectric Effect?

The PhotoElectric Effect is when light, or photons, hits a metal surface and causes electrons to be emitted from the surface.

2. Who discovered the PhotoElectric Effect?

The PhotoElectric Effect was discovered by Albert Einstein in 1905.

3. What is the significance of the PhotoElectric Effect?

The PhotoElectric Effect helped to prove the existence of photons and contributed to the development of quantum mechanics. It also has practical applications in technology, such as solar panels and x-ray machines.

4. How does the PhotoElectric Effect relate to the wave-particle duality of light?

The PhotoElectric Effect shows that light behaves as both a wave and a particle. The photons act as particles when they interact with the electrons in the metal surface, but they also exhibit wave-like properties in their frequency and energy.

5. Can the PhotoElectric Effect occur with any type of light?

No, the PhotoElectric Effect only occurs with certain types of light, specifically with high-energy photons such as ultraviolet and x-rays. Lower energy photons, such as visible light, do not have enough energy to cause the emission of electrons from a metal surface.

Similar threads

  • Introductory Physics Homework Help
Replies
25
Views
2K
Replies
5
Views
578
  • Quantum Physics
Replies
12
Views
669
  • Introductory Physics Homework Help
2
Replies
35
Views
1K
  • Introductory Physics Homework Help
Replies
4
Views
818
Replies
10
Views
2K
  • Quantum Physics
Replies
4
Views
854
  • Introductory Physics Homework Help
Replies
8
Views
2K
  • Advanced Physics Homework Help
Replies
1
Views
1K
Replies
13
Views
970
Back
Top