Photoelectric effect Definition and 385 Threads

I had a lab with photoelectric effect and we measured different colors wavelength/frequency by finding stopping voltage vs current. Then we used no color filter and used the mercury vapor lamp and had to find the wavelength which was around 400nm. Questions were why was this wavelength the...

what is the relationship between frequency and kinetic energy max ?

Hello Here is the problem I am trying to solve. Find the maximum kinetic energy of the photo electron liberated from the surface of lithium by electromagnetic radiation whose electric component varies with time as E=a(1+\cos \omega t)\;\cos(\omega_0 t) where a is constant and \omega =...

I am currently taking a quantum physics lab. The results from my most recent lab are troubling me. A quick description of the lab The setup includes an incandescent light bulb which feeds light into a monochromator. The monochromator consist of a couple mirrors and a diffraction grating. The...

Homework Statement In photoelectric effect, why the saturated current starts at the y-axis (0,y)? and what is the reason for that gradient at the negative x-axis (Shown as a red line)? Homework Equations - The Attempt at a Solution -

photoelectric effect is explained by taking photon of energy 'hv'.Even electromagnetic waves carry energy.Why can't they interact with electron and transfer energy ?Even a wave has characteristics frequency and wavelength charateristics and all. I think I'm a bit confused.Can someone help me...

Homework Statement 1. The kinetic energy of emitted electrons depends on the frequency, not the number of photons. 2. The energy of the radiation is proportional to the wavelength. 3. The number of emitted electrons depends on the number of photons, not the frequency of the radiation. 4. The...

I was solving a photoelectric effect exercise where we had to find the correct alternative. One of them was: The increase of the light frequency results in an increase of the intensity of the current that flows trough the circuit They were judging this wrong. But when we increase light...

What is the difference between the two ? Maybe that in the photoelectric effect all of the energy of a photon is absorbed by the electrons ? Is that it ? In Compton scattering, only part of the energy is absorbed hence there is a photon of lower frequency emitted ! OR Maybe in the...

If the energy of the photon is less than the work function of the metal, no photoelectric is observed. I would like to ask if the photon would be absorbed even if its energy is less than the work function? or the photon would not be absorbed?

I'm going over the photoelectric effect and have run into a conceptual problem, and was hoping for some help in resolving it. In particular, I am looking at the frequencies below the threshold frequency of whatever metal is being examined. So, because of the lower frequency, there will be no...

Hi... I have a quick question I'm not quite understanding. If I shine some light on a surface, metal or something, and the energy of the incoming wave is larger than the energy-barrier for the electron on the surface, an electron will be emitted. But my question is, if the incoming photon...

Homework Statement Electrons are emitted from a metal as a consequence of their absorption of energy from a light beam. Find the threshold frequency of the metal and the wavelength of emitted electrons. Wavelength of incident light λ = 500 nm Work function of the metal \phi = 2.1 eV Homework...

Homework Statement In a photoelectric effect experiment, the frequency of the light is increased while keeping the intensity of the light constant. What effect does this have? A) fewer electrons will be ejected B) more electrons will be ejected C) the same number of electrons will be ejected...

a light with frequency 'v' can't excite electrons from a metal surface if the threshold frequency of the metal is greater than the frequency of the wave( the light,electromagnetic radiation)so why don't the energies of the photons add up together and then excite the electron in the surface of...

Would the following explanations suffice to explain why the photoelectric effect shows the particulate nature of light? 1) There is instantaneous emission of photoelectrons when the energy of the photon is greater than the work function of the material. 2) There is no emission of...

Hello all when atom absorbed a photon , photon changes to virtual photon in atom and mass of atom must increase . but in other form electron absorbed the photon and pull off atom like photoelectric effect . My question is in photoelectric effect , mass of metal base increase or decrease and...

I get confused when I read that the Energy of wave in classical mechanics is correlated to the amplitude E ~ A^2 (pls. point me to a doc which shows that, couldn't find any exact formula on internet), but then when we are talking about atoms,photons,electrons they say it is dependent on the...

I have recently been reviewing the photoelectric effect in a circuit in which a metal target has a light directed onto it, and any resulting electrons flow through an empty space to a second target, completing the circuit to which a battery is also attached. I have, however, had a few conceptual...

Hi everyone, a quick question on photoelectric effect. Why measure stopping voltage by connecting a battery to the circuit and then adjust until current reach 0? Cant we just use a voltmeter? Thank you!

So in photoelectric effect, electrons can be ejected from a material when a beam of light shines upon the material, provided that the incident photons have enough energy to overcome the work function, i.e. hbar*omega has to be greater than W. Now, why can't I have n photons simultaneously...

Homework Statement In photoelectric effect, why does photon prefer K shell electron? Asked differently: In photoelectric effect, why does photon prefer electron of closest binding energy, rather than going for another electron of much lower binding energy? Homework Equations...

Using the photoelectric experiment,it is known that if light of same intensity but different frequency is used, stopping potential is changed and current changed. For instance,same intensity but frequency increased. E=hf, energy of photon increased which leads to a higher K.E of...

I have a question: A stopping potential of 0.5 V is required when a phototube is illuminated with monochromatic light of 490nm wavelength. The wavelength of a different monochromatic illumination for which the stopping potential is 1.50V is closest to： a) 350nm b) 330 nm c) 380nm d) 400...

Incident light on a PV cell generates both electricity and heat. That is because the incident light contains both visible and infrared light. If you can separate visible light and infrared light, and have only the visible light incident on the PV cell. Would the PV cell generate heat, when...

1. A scientist is investigating the effect of different types of radiation on the surface of a piece of Sodium metal. He uses a freshly cut surface on a Sodium plate. 2. a) Which of the variables is the dependent and independent variables? b) Why must the surface of the Sodium...

http://singlephoton.wikidot.com/single-photon-detection-experiment I was browsing the web earlier, and noticed that the page above said that recently there was a semi-classical (wave) explanation of the photoelectric effect (End of 2nd-3rd Line). I was wondering how this was, as I can't seem...

For the photoelectric effect, when light hits a metal, and the frequency is above the work function, electrons are given off. I am curious if the metal becomes more and more positive if this happens. i.e oxidation without reduction??. For this question, assume that it is done in a empty...

I understand that in photoelectric effect, the energy of the whole photon is absorbed, freeing an electron. I don't understand why in the case of Compton scattering, the higher energy photon lost part of its energy instead of transferring the whole of its energy to the electron as in...

Only metals undergo photoelectric effect?

What are some things about the photoelectric effect that can not be accounted for in the wave model of light?

We talked about the photoelectric effect in class today. A follow up conversation outside of class started among a few of us, and I'm having trouble sorting through literature on the subject to come to a clear conclusion. It seems pretty intuitive that if I heat up a piece of metal, all of...

OK, so i have a question about the nature of light, in the context of the photoelectric effect. So when photons are incident on a metal, given that they have a high enough frequency they can cause electrons to be emitted from the metal. Now i know that intensity of light is to do with the...

I am doing a science project on the photo electric effect (the experiment is the correlation between frequency, intensity, and electrons released.) My one problem is that I need some way to measure the free electrons. I was thinking a simple circuit with an anode plate and a cathode plate with...

I have the fifth edition of 'Physics' by Halliday, Resnick and Krane. In the chapter 'The Nature of Light' it is stated that it is possible to explain both photoelectric effect and Compton effect in classical electromagnetic wave theory and this has been known since 1927. It says that...

Homework Statement What is the maximum kinetic energy (in eV) of a photoelectron emitted when a surface, whose work function is 5eV, is illuminated by photons whose wavelength is 400 nm 1. -1.89 2. 1.89 3. 0 4. 3.1 Homework Equations hc/(lambda)=work function + KE max The...

i graphed cut-off voltage verses frequency. when i figured out plank's constant so when i calculated the slope of the function i got 4.224x10-15. My question is how to convert V.s to J.s for the value of hhereS the question FINDING A VALUE OF PLANK'S CONSTANT FORM YOUR GRAPH. calculate the...

hi i was thinking about the photoelectric effect, that we discussed in school: we said that, when a photon enters, it has an energy and this energy is used for electron binding energy and kinetic energy. so far so good. but how is it possible, that the electron is emitted in the opposite...

I read earlier that the photoelectric effect is when electromagnetic radiation essentially overcomes an electrons binding energy and converts it to electricity, which is how solar panels function. But why is it that gamma radiation isn't being used to capture energy? If gamma radiation has a...

The information I'm given is: frequency of light: 9X10^14 Hz magnitide of VA 1.3 V (not sure what this is, maybe stopping potential?) It says to simply state the max KE of the electrons so it must be quite simple but I just don't see it. I tried E=hf but this doesn't give max KE. Must have...

[SIZE="2"]About a week ago in class, I was learning about the photoelectric effect. My teacher described it as the emission of electrons as a consequence of their absorption of energy from electromagnetic radiation, etc, but later on I had a doubt: I know there's minimum frequency, for a given...

Homework Statement Consider a photon that is barely capable of causing a photoelectric effect when it strikes a sodium plate having a work function of 2.55eV.Homework Equations Find the minimum energy level n for a hydrogen atom that can be ionized by such a photon, and the speed of the...

Hello, I apologize if this question makes no sense, or is stupid, but I would just like to clarify something. Is the light that comes from the sun a high enough intensity to "knock" any electrons out of the atoms in a metal? I know it is a high enough frequency, and I think the intensity is...

Assume fmin is the minimum frequency of photon required for the electron to be ejected. Why can't we have an electron absorbing 2 photons of frequency fmin/2 thus the total energy will be 2h*(fmin/2)=h*fmin thus the electron to be ejected?

Homework Statement In a photoelectric effect experiment, 200.0 nm light was applied to a metal surface causing release of electrons. It was determined that a minimum 1.90V opposing electric potential was required to prevent the released electrons from striking the collection electrode. Based...

Photoelectric effect -- experimental Homework Statement Suppose you are doing an experiment to determine the work function of a metal.* You get k.e.$_1$, $\nu_1$ and k.e.$_2, \nu_2$. * We know that k.e.= $h\nu - W$ but when you solve the simultaneous equations, we have a $h$ slightly...

Homework Statement In an experiment with the photoelectric effect, the kinetic energy of the expelled electrons was measured. Draw a graph using this data and find the Planckconstant. Data: f(1014)hz : 5, 7, 9, 11 Ek(10-18)J: 0.07,0.19,0.3,0.43 Homework Equations well, Ek + W = hf...

Homework Statement Light with wavelength 452 nm illuminates a surface. The work function of the surface is 5.77 electron volts. 1. What is the frequency of light hitting the surface? 2. What is the maximum kinetic energy of the electron ejected from this surface? 3. What backing...

Homework Statement Photoelectric effect A beam of blue light falls on the cathode of a photocell so that electrons are emitted. The blue beam is then replaced by a yellow one with the same intensity and electrons are also emitted. What would happen to each of the following physical...

Hi, I'm studying quantum theory now and one thing I couldn't understand is why the frequency (and not the intensity) is the only respon sible for starting the photo eletric effect? I didn't understand this expression E total = E0 + E kinetic E0 = work functio n []'s John