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Photons

A photon is an elementary particle. Photons have zero rest mass which allows long distance interactions. The photon is massless, has no electric charge and is stable. A photon has two possible polarization states. Similarly to other elementary particles, photons are best explained by quantum mechanics and wave-particle duality.

A photon moves at the speed of light and its energy and momentum are related by the equation E = pc, where p is the magnitude of the momentum vector p. The energy and momentum of a photon depends only on its frequency or inversely, its wavelength:

E= ℏw=hv= hc/λ

p= ℏk

Where k is the wave vector, w = 2πv is the angular frequency, and ħ = h/2π is the reduced Planck constant.

Photons have applications in modern day technology. The classic photomultiplier tube exploits the photoelectric effect and photons landing on a metal plate. This principal is used in fire detectors. Other detectors use the ability of photons to ionize gas molecules causing a detectable change in conductivity.

Atoms, Energy, and the Periodic Table

Assignment Chapter 7 Concept Explorations 7.23. Light, Energy, and the Hydrogen Atom • a. Which has the greater wavelength, blue light or red light? • b. How do the frequencies of blue light and red light compare? • c. How does the energy of blue light compare with that of red light? • d. Does blue li

Photon numbers

The entrance exposure during a mammography examination is 100mR. (a) Suppose the photon bean consists of photons each of energy 20 keV. How many photons are incident on a 1 cm^2 surface of breast tissue? (b) Now suppose the energy of each photon is 50 keV. How many photons are incident on a 1 cm^2 surface of tissue?

Estimating the Wavelength of Visible Light

Please help with the following physics problem. The lowest energy visible light photon is the longest wavelength at the red end of the light spectrum. How many times greater is this energy than that of a typical microwave photon with a wavelength of 10^7 nm?

Statistical Distance vs. Actual Distance

Y Statistical Distance vs. Actual Distance, I am grappling with this concept and need a succinct explanation of the difference between statistical distance vs actual distance with some examples of how to calculate the numerical values for each distance. If you are ok with this project let me know and we can arrange a fee

Energy density in cavity radiation as a function of frequency

2. The sun radiates approximately as a black body or a cavity radiator at 5800 K. a) Find the frequency at which the energy density is maximum as a function of frequency, b) Find the wavelength at which the energy density is a maximum as a function of wavelength. c) Find the frequencya t which the photond ensityi s a maximu

Initial and Final States of Hydrogen

A hydrogen atom in an excited state emits a photon of wavelength 95 nm. Select the initial and final states of the hydrogen atom. 1 2 3 4 5 6 7

AMANDA 677 photon multiplier tubes

Please explain the answer for this problem. 1) The AMANDA 677 photon multiplier tubes embedded within the polar ice sheet to depths of over 2km. These tubes use the photoelectric effect to detect light. The metallic light-receiving surface within each tube is sensitive to light of wavelengths shorter than 605 x 10^2nm. The co

Photon Energies and Balmer Series

(See attached file for full problem description) --- Note on problem solving. A handy way to calculate photon energies and wavelengths is as follows: We know E = hc/lambda and  = hc/E for photons. The quantity hc may be expressed as 1240 eV-nm. Thus, a 2.0-eV photon as a wavelength lambda = (1240 eV-nm)/(2.0

Photon and photoelectric effect

Electromagnetic waves, with frequencies ranging from 4.00 x 10^14 Hz to 9.00 x 10^16 Hz, are incident on an aluminium is 4.28 eV, find (a) the maximum kinetic energy of electrons ejected from this surface and (b) the range of frequencies for which no electrons are ejected. Please work this problem out. I don't understand how

Thin-Film Interference

We have not covered in class yet and the book does not offer much help. Is it asking for the value (m)? If so how is that determined? Thanks. Light of wavelength 616 nm (in vacuum) is incident perpendicularly on a soap film (assume n = 1.36) suspended in the air. What are the two smallest nonzero film thicknesses (in nm) f

Photoelectrons produced by beams of light

Two beams of light with different wavelengths (A > B) are used to produce photoelectrons from a given metal surface. (b) Find Kmax for cesium (W0 = 1.9 eV) if A = 570 nm, and B = 330 nm. Kmax, A ___ eV Kmax, B ___ eV

SOME USEFUL TIPS ON x RAY PRODUCTION

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Energy of a photon of visible light given wavelength

If Planck's constant has a value of 3.99 x 10 to the -13 kJ sec/mole, and energy=Planck's constant x velocity of electromagnetic radiation (in nm/sec) all divided by wavelength in nm. What is the energy of a photon of visible light with a wavelength of 600 nm?

Positrons and Other Antiparticles

A photon with an energy of 2.00 GeV creates a proton-antiproton pair in which the proton has a kinetic energy of 95.0 MeV. What is the kinetic energy of the antiproton?

Wavelength of Electrons

A beam of electrons (m=9.11 x 10 (-31) negative thirty first power has an average speed of 1.3 x 10^8 (eigth power) m*s (-1) s to to the negative first power. What is the wavelength of electrons having this average speed? ^=____________________________m Assume your eyes receive a signal crossing of blue light, ^=470nm

Wavelength questions

You are an engineer designing a switch that works by the photoelectric effect. The metal you wish to use in your device requires 6.7x10 (to the -19 power. J/atom to remove an electron. Will the switch work if the light falling on the metal has a wavlength of 540nm or greater? Why or why not? Radiation in the ultraviolet re

Human eye and photon energy

The human eye can detect as few as three photons of 5.5X10^-7m light arriving together. How much energy do these three photons collectively represent?

Kinetic energy about a released electron

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