Work function Definition and 87 Threads

Homework Statement The maximum kinetic energy of photoelectrons is 3.14 eV. When the wavelength of the light is increased by 50.0 %, the maximum energy decreases to 1.11 eV. What is the work function of the cathode? Homework Equations Kmax = E elec - E not = hf - hfnot hf =...

Hi guys, I am currently in doubt with the relationship between the stopping potential and the intensity of light. Theoretically, I understand there should not be a relationship between these two variables, given that stopping potential is completely independent of light intensity. However, I...

Homework Statement During successive illumination of a surface of a particular metal with radiation of wavelengths \lambda _1 =0.35 \mu m and \lambda _2=0.54 \mu m, we find that the respective maximum velocities of the photoelectrons have a difference between each other of a factor 2...

Hypothetical device: Vacuum Tube Two tungsten electrode plates at each end The work function of tungsten is ~4.5V. Lets attach a power supply to the two electrodes with a potential difference of 4.0V. Question is, by biasing the two plates in such manner, is the thermionic discharge...

Work function is the energy to remove 1 electron from Fermi level out of the system. From the about definition, it seems that work function ought to be spin-independent. However in the electron configuration, the spin up is filled first and spin down is fill later. In result electron with...

Much easier if I just write it without the given templates. Well, I am not exactly the good at Physics, so I've decided to ask people that are good at it. I know Ekmax = hf - work function. I am just wondering what could prevent the electron from attaining it's maximum kinetic energy. Oh...

Homework Statement Monochromatic light with a wavelength 415 nm strikes a metal surface. Photoelectrons escape with a kinetic energy of 95 kJ/mol. What is the work function (in kJ/mol, no decimals required) of the metal surface? Homework Equations I have found various equations online...

I have recently graphed my Planck's Constant data from my Planck's Constant kit on Excel. The R squared value is great but there are a few things that confuse me. 1. I presume that the Equation of V = f(h/e) - W/e can be used with y = mx + c If so, then I presume that my equation of y = 3e-15x...

Hi Guys, I wanted to do an experiment testing the photoelectric effect but am having trouble getting light with energy higher than ~4 eV(300nm) through my window into vacuum as it's made of BK7 instead of something like fused silica. Does anyone know of a good material to use with a work...

Homework Statement Red light of wavelength 670 nm produces photoelectrons from a certain material. Green light of wavelength 522 nm produces photoelectrons from the same material with 1.2 times the previous maximum kinetic energy. What is the material's work function? answer in units of eV...

Homework Statement When a monochromatic light with a wavelength of 254 nm falls onto the surface of a particular metal it causes a photocurrent to flow. A stopping voltage of 2.30 V is required to completely block the photocurrent. What is the work function of the material? Homework...

Homework Statement The American physicist Robert A. Millikan (1868-1953) won the 1923 Nobel Prize in physics, in part for his work on the photoelectric effect. Assume that Millikan observed for a hypothetical metal a maximum kinetic energy of 0.535 eV when electrons were ejected with 431.7 nm...

How do you calculate the thermionic work function of an element (hydrogen for example)? I understand it is usually about 1/2 the ionization energy , but is there a formula to get the exact energy? Can hydrogen even have a work function? Thanks in advance.

Homework Statement a. Which plot on the graph represents the metal with the lowest work function? b. What does the slope of the graphs represent? (graph is attached) Homework Equations threshold frequency= work function/ planks constant The Attempt at a Solution a. the lower...

Homework Statement A certain photoelectric surface has a threshold frequency of 4.62 X 10^14 Hz. a) What is the photoelectric work function in joules? b) The surface is illuminated with light that has a frequency of 5.2 X 10^14 Hz. What is the kinetic energy of the electrons ejected from the...

Homework Statement Barium has a work function of 2.48 eV. What is the longest wavelength of light that will cause electrons to be emitted from barium? Homework Equations W = hf○ hf = W + Ek E = hf = hc/λ The Attempt at a Solution 1 eV/1.6e-19 C = 2.48/X X = 3.97e-19 W=hf○...

This is the case with metals semiconductors polymers and ceramics I have checked on the web. Still looking for exceptions...

Hello, everybody, I need to know the work function of anatase TiO2, can anybody tell me? and do you know any website or literature lists out the work function of many substances? Thank you very much. Best wishes.

Maximum work function?? Homework Statement What is the maximum work function for a surface to emit electrons when illuminated with 900nm infrared light? Homework Equations K= 1/2mv2 = hf - work function wavelength =h/p = h/mv The Attempt at a Solution p=h/wavelength =...

Homework Statement The wavelength associated with the cut-off frequency, for silver is 325 nm. a) What is the work function for silver? b) Find the maximum kinetic energy and speed of the electrons ejected from a silver surface by ultraviolet light of wavelength 254nm Homework...

The wavelength associated with the cut-off frequency, for silver is 325 nm. a) What is the work function for silver? b) Find the maximum kinetic energy and speed of the electrons ejected from a silver surface by ultraviolet light of wavelength 254 nm. So far for part a) i have: f = c /...

An ideal gas originally at a temperature T1 and pressure P1 is compressed recersibly against a poston to a volume equal one-half of its original volume. The temperature of the gas is caried during the compression so that at each instant the relatoion P=AV is satisfied, where A is constant. Find...

Homework Statement Let's just say some photons hit the anode in a photo-tube, and the light's frequency is the threshold frequency. Will the electrons have momentum when they leave the electron? Or will they simply leave the electron, only to come back because of the closer proximity...

Negative work function?? Hello, I'm studying the photoelectric effect from the book of Zettili. It has an example that calculated the work function of lead knowing the maximum kinetic energy of the phtoelectrons (8.57 eV) for a given incident wavelength (280 nm). The result is W = - 4.14 eV...

what is the work function for Aluminium Oxide?

For metals, work function is defined as the energy gap from fermi level to the vacuum level and electrons can escape from material if they have a certain mount of kinetic energy that is larger than the work function. But, how can we define the work function for the semiconductor or it is totally...

1) The maximum kinetic energy of photoelectrons is 2.8eV. When the wavelength of the light is increased by 50%, the maximum energy decreases to 1.1 eV. What are the "work function" of the cathode and the "initial wavelength"? K.E.initial=K.E.max=2.8eV=4.48x10^-19J...

I really need help with the following question, If the work function of Rb is 2.09 eV, what is the number of electrons ejected, their energy in eV, and their velocity, from a microjoule pulse of 500nm laser light?

Can someone explain the difference to me? Is it correct that the binding energy is the energy needed to bring an electron to the fermi level, and the work function it the energy needed to bring an electron from the fermi level to the vacuum level? What are typical values of the binding energy...

Apologies, but I have another photoelectron question. In this one I get a result that seems reasonable, however it does not show up on my list of work functions that I have available to choose from. The problem is: A photoelectric-effect experiment finds a stopping potential of 1.93V when...

The maximum kinetic energy of photoelectrons is 3.30 eV. When the wavelength of the light is increased by 50%, the maximum energy decreases to 1.50 eV. What is the work function of the cathode? What is the initial wavelength? K= E_elec - deltaE K_max = hf - E_0 = E_elec - E_0 f =...

A light source of wavelength lambda illuminates a metal and ejects photoelectrons with a maximum kinetic energy of 1.00 eV. A second light source with half the wavelength of the first ejects photoelectrons with a maximum kinetic energy of 4.00 eV. What is the work functin of the metal? I...

Do Ionization Potential values include or exclude the work function of the electron removal process? For example: The IP value for hydrogen is 13.6 eV. Is the true IP 13.6 eV or 13.6 - WF (ca. 4 eV) = 9.6 eV roughly?

The photocurrent of a photocell is cut off by a retarding potential of 2.92V for radiation of wavelength 250nm. What is the work function of the photoemitter? I want to use the equation: PHI=hc/lambda-Ve, where V is the stopping voltage (sorrry I don't know how to do the Greek letters for...

Quantum Mechanics Question -- Work function and h The maximum energy of photoelectrons from aluminum is 2.3 eV for radiation of 200 nm and 0.90 eV for radiation of 259 nm. Use these data to calculate Planck's constant and the work function of aluminum. Do I have it right?: E_{electron} =...

Problem 18. The threshold frequency of silver is 14.3*10^15Hz. What is the work function of silver? Answer in eV.

[SOLVED] Work Function .- Does anybody know a reference for an intuitive model of the work function? If not, is there a simple quantum mechanical model for it? .- Does anybody know of a simple model for a solid - electrolite interface?. .- What about a metal - metal interface?. .-...