Photoelectric Definition and 426 Threads

Homework Statement In an xray tube, a potential diff. of 70000v is applied across two electrodes. Electrons are emmited from cathode and acc. to anode, where x-rays are produced. my question is if the photoelectric effect problems apply and how they apply. (i.e use work function or E=hf)...

Hi. I hope someone can help. Here is the problem: [Pennies are made of zinc coated with copper. Copper has a work function of 4.7eV. The ozone layer blocks nearly all solar radiation with wavelength shorter than 320nm, but a very small amount of 200nm light still manages to reach the Earth's...

Help on "Photoelectric Effect" problem a] A beam of light of wavelength 400nm and power 1.55mW is directed at the cathode of a photoelectric cell. If only 10% of the incident photons effectively produce photoelectrons, find the current due to these electrons. b]If the wavelength of light is...

I'm not sure if I'm posting this in the right forum, so I apologize in advance if I'm not. I just have a question about the photoelectric effect. As I understand it, the photoelectric effect is where light/photons can knock electrons off a metal surface. I think that the intensity of the light...

[SOLVED] Photoelectric effect, retarding potential Homework Statement If the photocurrent of a photocell is cut off by a retarding potential of 0.92 volts for monochromatic radiation of 2500 A (A with the little circle above it), what is the work function of the material. Homework...

Homework Statement Light of intensity 1.5 x 10 (x)-2 Wm/2 and wavelength 250 x 10 (x)-9m is incident on an iron surface of area 1 x 10 (x) -4 m2. The iron surface reflects 95% of the light. The threshold frequency for iron is 1.1 x 10x15 Hz. Calculate: 1) The intensity of light available for...

What property of light does the photoelectric effect display?

Homework Statement Having some problem with this question: The threshold fequency for a material is 5.0*10^14 Hz. Find (a) the work function and (b) the maximum velocity of electrons ejected by radiation of frequency 8.0*10^14 Hz. The mass of an electron is 9.1*10^-31kg. Homework...

Homework Statement 1. How can Planck's constant and the work function be determined from the following graph? http://img507.imageshack.us/img507/9076/untitledgo5.jpg 2. Calculate the frequencies corresponding to the cut-off wavelengths for filters 15 and 29 in table 1. Take speed of...

Hi I'm a materials engineer and we have a subject about the optical and electrical properties of materials. In this subject I was asked a challenging question. I hope this is the right section for it. We were asked why gamma rays do not exhibit true absorbance in metals whereas ultraviolet...

I am having a bit of trouble understanding how a cutoff frequency would support the particle theory of light over the wave theory?

Below is my understanding of photoelectric effect, please correct me if I am wrong. It is an quantum electronic effect in which matter emits electrons after receiving energy in the form of EM waves. E.g. imparting X-rays on matter. So if we impart a high frequecncy wave (say f1) on a metal...

Homework Statement What will be the electric charge of an isolated ball of copper, which was projected long enough with radiation of wavelength \lambda = 1400 \angstrom? Homework Equations The radius of the ball is R=1cm and the work function of copper is \Phi = 4.47 eV. The Attempt at...

The Question: Find the maximum momentum of the electrons emitted from the surface of the Li metal, under the projection of the metal with EM radiation, when the electric component of the radiation is a function of time: E(t) = a(1+cos[w*t])*cos[w0*t] a= 18 [V/m] w= 6E14 [1/sec] w0= 3.6E15...

As the temperature of a body is increased, how does the frequency of peak intensity change? How does the total amount of radiated energy change? When the dimmer control is used to increase the voltage to the bulb, the temperature of the glowing filament increases. As a result, the color...

1. Light of a wavelength 410nm is incident on a metal target and an electron is eject from the surface. The work required to remove this electron from the metal is 3.0 x 10^-19 J. The elctron then travels straight to a collection plate. The different in electric potential between the collector...

Hi all, I would really appreciate any explanation on how these two are interrelated. Thanks. Preferably in simple terms. Nish

I am having trouble figuring how the info given relates to electric and magnetic fields. Homework Statement A laser emits 1.38x10^18 photons per second in a beam of light that has a diameter of 1.96 mm and a wavelength of 518.0 nm. Determine each of the following for the electromagnetic wave...

Homework Statement From the following graph determine the experimental value of the h/e ratio and the work function of the metal. ( 1 Joule = 6.242 x 1018 eV ) https://chip.physics.purdue.edu/protected/Prelab221img/e9pp41.jpg The work function Wo in eV from the y-intercept of the...

A 0.4 kilogram sample of Aluminum at 115 degrees Celsius is put into a container containing 0.5 kilograms of water at 15 degrees Celsius. Neglecting the small amount of energy absorbed by the container and knowing that the specific heat of Aluminum is 900 kJ/kg*C, and the specific heat of the...

Let us consider the photoelectric effect described on http://hyperphysics.phy-astr.gsu.edu/hbase/mod1.html/" . A photon has an energy of 2.25 eV and produces a photoelectron effect on a potassium target, the maximum energy of the photoelectron is 0.50 eV, indicating the photoelectric...

Homework Statement 3. The classical radius of an electron is 2.82 x 10^-15 m. If a material is radiated with sunlight with an intensity of 500W/m^2, calculate using classical arguments the time required for an electron to gain an energy of 1eV. How does this result compare with electron...

Homework Statement In an advanced laboratory class a student performs the photoelectric experiment. Ultraviolet light is shone on a particular metal and the stopping potential is measured at the same time. It is found that 2.61 V is needed to stop all the electrons when the wavelength of the...

Homework Statement Light is incident on the surface of metallic sodium, whose work function is 2.3 eV. The maximum speed of the photoelectrons emitted by the surface is 1.08 106 m/s. What is the wavelength of the light? Homework Equations e=hf p=h/wavelength The Attempt...

Once electrons are ejected via photoelectric effect, the eventual recombination of the holes they leave behind is not discussed much (maybe not even at all) in textbooks. Also important, where they recombine as well as how long after the e-h pair formation.

Hiya, I'm about to teach the photoelectric effect in class. Everybody knows that observations contradict the classical prediction. Which is: Stopping voltage schould go up with light intensity. OK. But I have a problem: What EXACTLY is the classical prediction? I mean, is there a formula that...

The Photoelectric effect and "classical physics" The kinetic energy of the ejected electrons predicted by the classical physics should be related to the intensity of the light. According to experimental results, the kinetic energy of the electrons is proportional to the frequencies of the...

A sinusoidal EM wave which length l is very great, hits a photoelectric device. According to HUP, a sinusoidal EM wave with finite length l has a spectrum of frequencies which broadness is inversely proportional to l. So, if l is very great, the energy uncertainty is very low, and this, still...

:confused: why can't wave nature of light explain photoelectric effect?

Light is incident on the surface of metallic sodium, whose work function is 2.3 eV. The maximum speed of the photoelectrons emitted by the surface is 1.26e6 m/s. What is the wavelength of the light? I first converted Work Function to Joules: 2.3eV x (1.6e-19 J / 1eV) = 3.68e-19 J The...

White light (ranging in wavelengths from 380 to 750 nm) is incident on a metal with work function Wo = 2.46 eV. (a) What is the maximum kinetic energy of the electrons emitted from the surface? KEmax = eV E = hf = hc/lamda. E = (6.626*10^-34)(3*10^8) / (750*10^-9) = 2.6504E-19...

What is the main differences? Are they essentially the same thing? From what I have gathered, the two are fundalmentally the same. If a photon gives up all its energy after interaction with an electron than the photoelectric effect applies. On the other hand if the photon continues to travel...

Hello my question involves what exactly is the frequency and intensity of the light. The E = hf applies to the photon particle aspect of light right? So where is f from, the wave aspect? Also increase f, which increases E makes the electrons eject faster in terms of kinetic energy right, but...

Hi guys, I've got a little conceptual question here. I became a little confused after my exam. Firstly, I understand that in the photoelectric effect, the electrons either accept all or none of the energy from the particular incident photon and the photon must have a minimum frequency...

Hi guys, I've just returned from my exams.. I thought it was pretty alright but I think it could've been better. I was stuck with this question. A photoelectric experiment was set up. Monochromatic light is incident on a metal plate, and the photo-electrons are collected at a electrode...

Apologies if this has come up before, but a week or so ago I read a paper or article that said the photoelectric effect was not necessarily a particle phenomenum after all, despite Einstein's Nobel prize. I didn't pay much attention to it because I was interested in something else at the time...

We have been doing some experiments using a mercury light source and filters for each wavelenght and a Detector Box (phototube) to measure the output voltage, to investigate planks constant, stopping voltage, intensity's effect... the typical - "energy is quantised" idea. :zzz: There is one...

i know theses qns may look lame but my answers are not matching with the book .pls help as i have a MAJOR EXAM coming up tomorrow:eek: 1.three photons are coming out from an excited ample of hydrogen atoms with energies of 12.1 10.2 and 1.9 eV respectively then which of the following is...

I am just trying to wrap my mind around this. Einstein explained the effect using photons, but why couldn't the electron get stripped by a wave. I understand that the electron will not get stripped until the energy is high enough, but I don't understand why a wave could not be resonsible. It...

Bremsstrahlung is the process in which an accelerated electron radiates and loses energy in the form of a photon(production of continuous X-rays). In photoelectric effect, an atom absorbs a photon and an electron from one of the shells is ejected. So, is it reasonable to regard X-ray...

Im trying to get my head around a question in a book as i thought it would be good to give them ago as I am struggling. The question is: Explain why a metal plate does not lose its charge when; a) the plate is + charged and illuminated with visible light. b) the plate is - charged and...

hello from my understanding of the photo electric effect, the minimum workfunction must be met before electrons are emitted prior to that, intensity doesn't play a part. if the frequency is increased to juz above the work function and stays constant there and i increase the intensity...

Hi, Can someone point me to a treatment of the preferential direction of emission of a photoelectron in the case of polarized incident light ? I think that there is a relationship a la cos^2 theta between the plane of polarization of the light (E-field) and the probability of emission of the...

I have some questions regarding the first two sections Einstein's paper. I'd really appreciate some guidance. The paper can be found here: http://lorentz.phl.jhu.edu/AnnusMirabilis/AeReserveArticles/eins_lq.pdf In section 1 of the paper, he considers a volume of gas surrounded by...

When a photon with the right frequency hits the electron of an atom. At what portion does the wave function of the atom collapse. Is it when the photon enters the atomic space or when the photon hit the potential electron probability location?

How would I find the threshold frequency if the work function is 3.33eV? I know how to calculate minimum frequency.

what can be said about the work functions of two metals when the threshold wavelength in the photelectric effect increases. I'm having trouble finding and equation to describe this relationship. ANyone have any ideas?

My question is simple: What is the metal(s) used in photoelectric experiments? Textbooks just put a tiny metal foil. Any answer would be appreciated. Thnx.

The photoelectric equation is given by: hf = hf0 + 1/2mv2 where f is the frequency of the incident wave and f0 is the threshold frequency. HERE, only the conservation of energy is taken into consideration and momentum conservation is neglected. Why is this approach justified? Suppose we...

So i have this problem. An isolated copper sphere of radius 5.00cm, initially uncharged, is illuminated by ultraviolet light of wavelength 200nm. What charge will the photoelectric effect induce on the sphere? The work function for copper is 4.70 eV. Can someone help me conceptualize...