For the work function, is it taken into consideration that the metal has oxidized, giving it a different energy to release the electron? Or is it so small that it is negligible?
Elements like Silicon, Germanium and Gallium can be used to make solar cells but platinum can not be used.
What is the exact reason? Is it related to threshold frequency?
Tried to search for the answer through many sources, but couldn't get a satisfactory one.
Your views and answers are really...
The minimum energy required to eject an electron from the surface is called the photoelectric work function.To be precise to eject means force or throw (something) out
So energy equal to work function would surely eject an electron from metal surface
but according to the video below
At time...
What materials and equipment would be needed to for a hobbyist photoelectric effect lab kit?
If possible, trying to keep this within a budget of $50. (Cheaper if feasible).
Hello!
First of all, this is my first post here. I hope it's on the right thread.
I managed to answer most of the questions, but I think at least some of them are wrong (for example, d)). Any help would be really appreciated.
Homework Statement
A monochromatic light beam of wavelength λ=500nm...
The kinetic energy of a photoelectron is independent of the intensity of the light.
If we increase the intensity of the light, the effect is, the number of photons arriving will increase and in turn we will eject more photoelectrons. However, the maximum kinetic energy of anyone photoelectron...
In the photoelectric effect, we observe that the stopping potential is independent of the intensity of the light. This is readily explained by the photon hypothesis. One often sees the statement that in "the classical theory," the stopping potential should increase with intensity.
What...
I'm currently self-studying quantum mechanics and instead of starting a new thread every time I have a new question I figure I'd just make one thread dedicated to all of them.
I'm going over the Photoelectric Effect. The way I understand it is when light is shone on a metallic surface, the...
I learned that photons can exite and ionize electrons in an atom, bring them to higher energy level etc. However I've seen a few questions on electrons bombarding electrons in an atom and exiting the orbital electrons to higher energy level.
Is this the same as the photoelectric effect when...
Hello!
I've read that electrons can only absorb photons of exactly the right amount of energy to move to a higher energy level, if its to little or too much then it doesn't absorb it at all, so my question:
How can electrons be liberated from an atom with Kinetic energy when they can't absorb...
Homework Statement
A photon with of 13600eV energy interacts with a hydrogen atom at rest and ejects the electron (photoelectrically) in the direction in which the photon was travelling. If 13.6 eV is required to eject the electron, find the speed of the photoelectron and the momentum and...
Homework Statement
I'm trying to determine Planck's Constant through an experiment with the Photoelectric Effect, however, the equations I'm given and the data I've collected are not getting me to the 6.63e-34 that I need to be at. I'm graphing Stopping Potential (V) vs 1/λ and then using the...
Recently I've seen claims here on PF(from some highly trusted members), that photoelectric effect can be described without using the photon concept and so can't be a demonstration of the quantized nature of light. This demonstration is only provided by more advanced experiments.
After that, I...
Homework Statement
"During a laboratory experiment with photoelectric effect, a metal plate is irradiated with light. The voltage that completely stops the beam of electrons is then measured.
When the wavelength is 546 nm, the voltage is 0,38 V. When the wavelength is 410 nm, the voltage is...
I know what the letters mean, E = Energy of the photon, h = Planck's constant, f = frequency of the photon.
But what does it mean for a particle to have a frequency, something that I'd associate with a wave. And what can you think Planck's constant is representing?
Any replies would be much...
Homework Statement
In the photoelectric effect, it is assumed that a single electron absorbs a single photon. But, there is a certain probability that a single electron may simultaneously absorb two identical photons from a high-intensity laser. How would such an occurrence affect the...
Homework Statement
Find the speed of light using Planck's constant measuring apparatus
Homework Equations
E=h(frequency)
E=(h*c)wavelength
The Attempt at a Solution
Can I substitute E=mc2 and use the mass of electron in the equation?
Lets take a simple water molecule for example. You can use the photoelectric effect to remove electrons from a molecule. As a thought experiment, let's say you have a contained single water molecule in a vacuum with no impurities. Perfect Vacuum. If you use the Photoelectric effect and beam...
I'm not really sure where to put this question, but definitely this is just an introductory physics coursework. Let me refresh you first with the basics of the photoelectric effect.
We all know that in the photoelectric effect the stopping voltage is just the kinetic energy obtained by the...
Homework Statement
If I know the work function of various metals in eV and need to find the largest wavelenghts required to emit photoelectrons from the metals would i just use ɸ=hf0=hc/λ0?
Homework Equations
ɸ=hf0=hc/λ0
The Attempt at a Solution
The formula only gives the threshold...
From the post
https://www.physicsforums.com/threads/photoelectric-effect-saturation-current.720506/
and
http://www.thephysicsforum.com/quantum-physics/3921-photoelectric-current-dependence-potential-difference.html
I have some idea on why does a higher potential different will not increase the...
Homework Statement
I am doing the photoelectric effect experiment. And we were trying to verify the relationship between photoelectric current and distance is
I \times d^2 = k, where k is a constant.(At least I believe this to be true.)
But from the data, I kind of get a I= k d^{-2} + b . And...
When a cm thick surface is illuminated with light of wavelength lambda,the stopping potential is V. When the same surface is illuminated by light of wavelength 2lambda , the stopping potential is V/3.The threshold wavelength for the surface is ? Homework EquationsThe Attempt at a Solution
I was recently taught that the probability of the photoelectric effect occurring was proportional to Z^3 and E^-3 (where Z is the atomic number, and E is the energy of the photon). My understanding is that the photon's energy must be close to the binding energy of the inner electron to be...
Hi, how could i calculate the current I would get from the photoelectric effect, so that the end result would be in amps?
If I have a certain lightsource or source of powerful enough em radiation to conduct the photoelectric effect , how could I calculate the intensity needed for given current ...
I want to understand how this circuit demonstrating the photoelectric effect works. Please see attached picture.
On the picture we see light entering the cathode C, which, if the light is above the threshold frequency can eject electrons from the cathode, which hits the anode A, creating a...
When a fixed intensity and frequency Em radiation strike a metal plate , is the outgoing electron/s with a higher energy if the plate is charged to some potential (volts) than if the plate is simply neutral?
Hi, I am currently revising photoelectric effect, and i have this question:
A metal surface at zero potential emits electrons from its surface if light of wavelength of 450 nm is directed at it but not if light of 650nm is used. Explain why photoelectric emission happens with light of...
In a photoelectric cell, the stopping voltage is 2.00V. If the voltage applied across this cell is zero, what is the maximum speed of the electrons from the photoelectric surface?
Confused.
Homework Statement
With the work function of copper being 4.65eV calculate the kinetic energy of a photoelectron knocked out with a photon with wavelength of 200nm . Then calculate the velocity of the electron.Homework Equations
KE=hf-ø
The Attempt at a Solution
FIrst time I have done a...
Hi,
I have read that light could either behave as waves or particles but not both at the same time.
What will happen if we perform the diffraction experiment, but replace the screen with a metal whose work function is small enough so electrons could be ejected from the metal? Do we see...
First of all, Hi we haven't even learned the E = ((hc)/λ) in the physics class but we have this question on our test-exam and I hope that it's fairly easy:
Homework Statement
A metal plate is shone upon with a monochromatic light. When the wave-length is 550 nm a photo-electric effect is...
Hey guys, thanks for any help in advance. I'm working through some exercises in University Physics 13th Edition and have an issue with a photoelectric effect question.
I'm given a graph that represents stopping potential as a function of frequency of light falling onto the surface (attached is...
Homework Statement
Assume the same set-up to measure the stopping potential Vs through different filters. Suppose a filter allowed through only light of frequency fo (the cut-off frequency) or lower. In this case, what would the stopping potential be?
1) you cannot tell, since different...
Homework Statement
Suppose the following: the light source gets very hot (by increasing the intensity), what affect do the heated photons have on photoemission?
Possible choices:
1) they decrease the number of photoelectrons by heating the metal and raising the work function
2) none...
Homework Statement
Suppose a filter allowed through only light of frequency fo (the cut-off frequency) or lower. In this case, what would the stopping potential be?
Homework Equations
KEmax = (charge of electron)(stopping potential) = hf - Work function, where Work function = hfcutoff...
Grade 12 physics help. Any help would be greatly apprecitated. Thanks
1. A light source with a wavelength of 550 nm shines on photocells, each with a work function of 1.60 eV. What is the minimum number of photocells required to generate 5.25 ´ 10-19 J of energy?
2. Light with a frequency...
Hello all,
I have been searching the internet for quite some time now, and have been unsuccessful in finding some article that will explain WHY there is a saturation current. All I have found is the definition of the saturation current. I don't understand why the current becomes constant as...
Homework Statement
I'm trying to make sense of some data taken during a lab in which we were tasked with obtaining a value for Planck's constant by measuring different stopping voltages from varying wavelengths of light. The value I got was 3E-15 eV*s, but I know I can get a better value if I...
I've been reading through the posts on this forum that deal with the photoelectric effect as evidence for the quantization of the EM field. In all of the introductory texts I've read, the cut off frequency and the dependence of the photoelectron energy on the frequency of the light are...
Homework Statement
I am wondering, what happens to those photons ( all having same energy level) in a light beam when the photons don't have enough energy to release the electrons in the metal that are more tightly attracted?
Does the overall work function of the material decrease...
Homework Statement
When 445 nm light strikes a certain metal surface, the stopping potential is 70% of that which results when 410 nm light strikes the same metal.
Homework Equations
The Attempt at a Solution
$$P=0.7P'\\ \frac { nE }{ t } =\frac { 0.7nE' }{ t } \\ \frac { hc }{...
hi...
i found a number of similar thread posing the same question but i didn't get the answer i was looking for, so i am asking it again.
Basically, as far as i have understood photoelectric effect is about absorption of a photon by an electron and the extra energy converted to its kinetic...
Homework Statement
So I recently performed the photoelectric effect experiment in my physics class, where we measured the stopping voltage at different wavelengths of light by using filters with different levels of grating.
I measured the stopping voltage and plotted them on a graph against...
Textbooks say that by measuring the stopping potential V0, we can determine the maximum kinetic energy with which electrons leave the cathode: eV0 = Kmax
However, as I know, when we apply the stopping potential, the electrons will decelerate and radiate parts of their energies. Thus, the...
Provide one of the following answers: PE,CS, BOTH, OR NEITHER.
PE if the statement applies only to Photoelectric Effect.
CS if the statement applies only to Compton Scattering
BOTH if the statement applies only to both the Photoelectric Effect and Compton Scattering.
NEITHER if the...
If I write photoelectric effect equation to nhv = 1/2mv2 + W with n = 1,
I am puzzled whether the n is larger than 1, such as 2 or 3, for which I will get the two- or three- photon absorption.
Could you give me some comments on these question?
Best regards.
sandf