Photoelectric Definition and 426 Threads

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 In Lenard's experiment to determine e/m for photoelectrons, he puts forwards this equation mv2/2 = eV, where e is the charge, m is the mass of photoelectron, and V is the potential applied. Why the kinetic energy equation is equated to eV? Thanks in advance Homework...

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

Homework Statement Show that a free electron cannot absorb a photon and conserve both energy and momentum in the process. Hence, the photoelectric process requires a bound electron. (Eisberg and Resnick 2nd Ed) Homework Equations hv = E p = K / c E2 = (pc)2 + (m0c2)2 The Attempt...

Hi everyone, I've been reading bits about the photoelectric effect, about how when you shine a light on a strip of metal its spits out electrons etc. What do they mean by spits out electrons? Is it that it actually spits the electrons out? If so where do they go? The book I'm reading uses...

Homework Statement http://phet.colorado.edu/simulations/sims.php?sim=Photoelectric_Effect Part 6 1. Set the cathode metal to copper and light intensity to 50 %. 2. Tabulate eight values for frequency and photoelectron energy in Joule. 3. Draw a graph of frequency and...

What determines if the photoelectric effect occurs? There are several aspects on this topic that I don't really understand such as: - What is the relationship between the frequency of the incident photon, threshold frequency and the ejection of electrons? - What is the relationship...

Homework Statement I see graphs for the total mass attenuation coefficient such as this all over the web:http://scientificsentence.net/Radiations/images/attenuation_coefficients.jpg However, I can't find data on the individual attenuation coefficients such as the photoelectric or Compton...

Work function of metals: http://hyperphysics.phy-astr.gsu.edu/hbase/tables/photoelec.html#c1 Copper work function - 4.7 eV Silver work function - 4.73 eV Silicon work function - 4.26 eV (http://environmentalchemistry.com/yogi/periodic/Ag.html) The work functions of conductors are...

Homework Statement True/False: In the photoelectric effect, the cut-off (threshold) frequency depends on the intensity of incident light. Homework Equations hv = W + 1/2mv^2 v = W/h The Attempt at a Solution The threshold frequency depends on the wavelength of incident light...

What happens to the ions that are released from the material after e- are released? How come the material doesn't completely degrade?

Hi, In a double slit experiment, shooting a photon will produce interference pattern on a screen. Using a detector to detect which slit the photon passed through will destroy the interference pattern. The photon will pass through only 1 slit, and cause slit pattern on the screen. The...

First check out this picture (from the book I'm reading) http://imageshack.us/photo/my-images/838/25090635.png/ It says that the collector's voltage is decreasing , can you explain why? also it says "few photoelectrons can overcome this potential difference", since the potential...

Hi, I am interested to know if photoelectric effect happens in a "single atom" of say Iron which is in a vacum... ? if yes, what is the workfunction of Fe2+ ? If no what is the ionization energy of Fe2+ in eV? Thanks in advance.

Both Compton effect and photoelectric effect involves collision of photon with a electron. I don't understand why one has scattering but one is simply kicking out electron. The photoelectric effect said light can transfer it's energy only in quantized units of h bar, so why the photon in...

OK, so recently I have learned that in the early 20th century, while Max Planck was attempting to explain the quantum nature of light, two men named Philip Lenard and Heinrich Hertz discovered the photoelectric effect. They found that an electron must absorb a specific amount of energy...

Homework Statement Would 449-nm blue light eject electrons from silver metal with a work function of 4.74 eV? Homework Equations E = hc/lamba The Attempt at a Solution E = [(6.63*10^-34 J*s)(3.00*10^8 m/s)]/(4.49*10^-7 m) = 4.42*10^-19 J 4.42J/1.60*10^-19 J/eV = 2.77 eV...

Homework Statement A graph displays the kinetic energy of photoelectrons as a function of frequency of light falling on a cathode in a photoelectric cell. If the cathode is replaced with one of greater force of attraction to its electrons, describe how a graph of kinetic energy against...

Hello, This question is based on the passage to the left. Please I need some one to explain it to me in "baby steps" if possible. I already read another explanation of it .. (posted below the picture) but i still can't understand how the final kinetic energy will be the same as the initial...

Homework Statement A photocathode whose work function is 2.9 eV is illuminated with white light that has a continuous wavelength band from 400 nm to 700 nm. A) What is the threshold frequency for photoelectron production? a. 4 x 1014 Hz b. 7 x 1014 Hz c. 13 x 1014 Hz B) What is the...

Homework Statement Em radiation of frequency .88X10^-15 Hz falls upon a surface of work function 2.5 eV. A)Calculate Max KE B) If a nearby electrode is made negative with respect to the first surface using a pd V, what value is required for V if it is to be just sufficient to stop any of...

The following computer simulation http://phet.colorado.edu/en/simulation/photoelectric contains a serious error: if you in the saturation (U >> 0V) with the same intensity change the wavelength of light, the photocurrent also changes...

Homework Statement A photon with an energy of 15.2 eV enters a hydrogen atom in the ground state and ionizes it. With what kinetic energy will the electron be ejected from the atom? Homework Equations Photoelectric Effect equations. The Attempt at a Solution E=W+KE I don't...

First of all, I would like to apologize if this question is in the wrong section of the forums. I'm not sure if the photoelectric effect should go into "Quantum Physics", "Classical Physics" or even "Homework & Coursework Questions" Descriptions of the photoelectric effect commonly states the...

why does photoelectric effect show the corpuscular nature of light? can't we approach photoelectric effect phenomenon by regarding radiation as a wave? can't a wave just give the energy it carries to the electron causing it extracting? another question: with respect to...

1-if we want to increase the number of ejected photo-electrons, can we change the frequency of the electromagnetic radiation? 2-if i calculated the number of the ejected photo-electrons and the kinetic energy of each electron, how could i then calculate the voltage of this photoelectric cell?

Homework Statement Lenard's experiment on photoelectric effect concluded mvm2/2 = eVs where vm is the highest velocity of photo electrons and Vs is the stopping potential. From this he concluded maximum velocity of photo electrons depends only on the wavelength of light used and not on the...

Hello Before a photon hits an electron, the electron originally had a kinetic energy, if f = f0 we know that Kmax = hf -hf0 = zero shouldn't the electron's kinetic energy increase the photon hits it? not the converse?

Homework Statement Light of wavelength 5.4 * 10^-7 m falls on a photosurface and causes the emission of electrons of maximum kinetic energy 2.1 eV at a rate of 10^15 per second. The light is emitted by a 60 W light bulb. Homework Equations Find the work function of the surface...

We have the parameters,current =10^-3A,V=15kv,number of electrons=6.25 X 10^15,velocity=7.3 X 10^7,specific heat capacity of the liquid=2 X 10^3,c=3 X 10^8,h=6.63 X 10^-34,mass of electron = 9.11 X 10^-31. Now the question says,in an x-ray tube having those parameters,find the rate at which...

What exactly in the photoelectric and Compton effects can't be explained with the wave model of radiation? For instance in the photoelectric effect, why the fact that the energy of the electrons emited from a material after being subjected to certain radiation depends only on the frequency of...

Homework Statement A photoelectric effect experiment uses a light of frequency 8x1014Hz and a metal with a work function of 1.2eV. A 1.5V stop potential is also applied. What is the maximum kinetic energy of the emmited electrons? Homework Equations I was thinking about using Ek= hf-W...

Homework Statement Hi there. I have two questions and in both I believe that no photoelectrons will be emitted from the surface. Question 1 A metal with a work function of 9 x 10^-19 J is irradiated with UV radiation of wavelength 180 mm. Will photoelectrons be emitted from the...

Homework Statement Q. How much energy will it take to remove only one electron on the surface of Nickle? If you hit the surface of Nickel with a photon that has a wavelength of 90 nm, what will the wavelength of that ejected electron be? Homework Equations KE= 1/2 MV^2 \lambda=h/mv...

Hi there, I have this problem with this photoelectric effect experiment. In the image of my attachment particulates will be ejected from C and move to D. The electric field(by A and B) will change the particulates trajectory to A, B or will not change this? Thanks Tony PS: Sorry...

Homework Statement "A blue laser beam is incident on a metallic surface, causing electrons to be ejected from the metal. If the frequency of the laser beam is increased while the intensity of the beam is held fixed, a)the rate of ejected electrons will remain the same but the maximum...

Thought to put this here because of the wave-particle duality ties. My question, that I already asked a tutor was how come electron ionization is due to frequency, and not intensity. He told me that it was because of nature's "no free lunch" policy and that changing the intensity was just...

Homework Statement This has to do with a simple photoelectric effect setup: If there is no current, would increasing the frequency of the light result in at least some current? If there is some current, would increasing the frequency result in a maximum current? Homework Equations...

1. Is binding energy equivalent to work (W)? 2. A He-Ne gas laser produces monochromatic red ligth with a wavelength of 6.3 x 10-7. If the beam is reflected normally from a mirror, what is the change in momentum of each photon on reflection? I am particularly confused about this...

If the photoelectric effect causes light to knock electrons out of metals, why don't the metal surfaces in our home lose electrons when we turn on the light? I'm a third-year college student. This question was a discussion question in the back of the chapter, and I thought it was a great...

I'm sure I'm overlooking something simple here. I am trying to understand characteristic x-rays given off during photoelectric absorption of a photon. The energy from the photon is given to an inner orbital electron and the photon no longer exists. The electron uses the energy to escape, and...

Ok I'm doing some gamma ray spectroscopy and finding that the two main effects occurring are Photoelectric and Compton. I want to fully hash out similarities and differences for these two effects so I know exactly what's going on. As a starting point, I know that in the photoelectric effect the...

got a couple of questions... firstly, A blue supergiant star has surface temperature 29kK and has total power output 100000 times that of the Sun. where is the wein peak of this stars balckbody curve? I got lambda=9.99*10^-8m, which i know is right. now, radius of sun is...

Homework Statement A monochromatic light beam with wavelength \lambda =405 nm and intensity 3 \times 10 ^{-9}\frac{W}{m^2} points to one of the plates of a plane metallic capacitor (photocathode). We apply a difference of potential of 1.15V between the 2 plates in such a way that we slow...

Hey guys, assume that i performed and experiment to measure the maximum kinetic energy of electrons released due to the photoelectric effect due to light falling on a metal target (i.e. Sodium). KE = hf - W (where W = work function, f = frequency and h = Planck constant) since KE = 1/2...

Homework Statement Chlorophyll and the Photoelectric Effect I have been trying to put together a lesson on the photoelectric effect applied to biology and chemistry concepts, and have been unable to find an explanation for some things. Here is some background: When chlorophyll is...

1. The problem statement A hydrogen atom has an electron in the fundamental state. a. Show that a radiation with λ = 50 nm will ionize the atom. b. What will be the excess kinetic energy of the electron in joules? What is this question asking? Is it asking what wavelength will free...

i know that einstein explained it in terms of particles but can maxwells EM waves explain the photoelectric effect aswell?