Maximum electron energy against the frequency of the light
At its defaults it draws maximum electron energy against the frequency of the light. The greatest kinetic energy a photoelectron leaves with, against the frequency of the light, for caesium (work function 2.14 eV), calcium (work function 2.87 eV), zinc (work function 4.33 eV). The lines are parallel: their common slope is Planck's constant, 4.1357e-15 electronvolt seconds. Each line meets the energy axis at minus its own work function and meets zero at its own threshold frequency, below which no light of any brightness produces an electron.
photoelectric is one function in lib/figures/quantum.js —
the quantum of light and the wave of matter. Everything below came out
of it during this build, at parameters taken from the essays rather than invented for this
page. A figure here is the figure a reader meets in an essay, and if the generator changes,
this page changes with it.
At its defaults
Drawn even though every essay passes options, because a default nothing exercises is a trap for the next essay to call this with none — which has happened here twice.
The greatest kinetic energy a photoelectron leaves with, against the frequency of the light, for caesium (work function 2.14 eV), calcium (work function 2.87 eV), zinc (work function 4.33 eV). The lines are parallel: their common slope is Planck's constant, 4.1357e-15 electronvolt seconds. Each line meets the energy axis at minus its own work function and meets zero at its own threshold frequency, below which no light of any brightness produces an electron.
The wavelength shift against scattering angle
The options are the ones A photon with a momentum, and a collision that proves it passes. A branch drawn at its own defaults instead would be a picture no essay asked for and no assertion has been run against.
How much longer a scattered photon's wavelength is, against the angle it scattered through. The shift runs from nothing at 0 degrees to 4.853 picometres straight back, passing through the electron's Compton wavelength of 2.4263 picometres at 90 degrees. Nothing about the incident light or the target material appears anywhere on this axis.
One Compton scattering event, with its momentum triangle
The options are the ones A photon with a momentum, and a collision that proves it passes. A branch drawn at its own defaults instead would be a picture no essay asked for and no assertion has been run against.
An X-ray photon of wavelength 71.1 picometres arrives from the left, scatters through 60 degrees, and leaves at 72.31 picometres. The three arrows are the incident photon's momentum, the scattered photon's, and the electron's, drawn to one scale; they form a closed triangle because momentum is conserved. The electron carries off 0.29 kilo-electronvolts, which is exactly what the photon lost.
One Compton scattering event, with its momentum triangle
The options are the ones A photon with a momentum, and a collision that proves it passes. A branch drawn at its own defaults instead would be a picture no essay asked for and no assertion has been run against.
An X-ray photon of wavelength 10 picometres arrives from the left, scatters through 120 degrees, and leaves at 13.64 picometres. The three arrows are the incident photon's momentum, the scattered photon's, and the electron's, drawn to one scale; they form a closed triangle because momentum is conserved. The electron carries off 33.08 kilo-electronvolts, which is exactly what the photon lost.
One Compton scattering event, with its momentum triangle
The options are the ones A photon with a momentum, and a collision that proves it passes. A branch drawn at its own defaults instead would be a picture no essay asked for and no assertion has been run against.
An X-ray photon of wavelength 71.1 picometres arrives from the left, scatters through 150 degrees, and leaves at 75.63 picometres. The three arrows are the incident photon's momentum, the scattered photon's, and the electron's, drawn to one scale; they form a closed triangle because momentum is conserved. The electron carries off 1.04 kilo-electronvolts, which is exactly what the photon lost.
One Compton scattering event, with its momentum triangle
The options are the ones A photon with a momentum, and a collision that proves it passes. A branch drawn at its own defaults instead would be a picture no essay asked for and no assertion has been run against.
An X-ray photon of wavelength 2.5 picometres arrives from the left, scatters through 90 degrees, and leaves at 4.93 picometres. The three arrows are the incident photon's momentum, the scattered photon's, and the electron's, drawn to one scale; they form a closed triangle because momentum is conserved. The electron carries off 244.26 kilo-electronvolts, which is exactly what the photon lost.
What checks it
physicscheck asserts something about photoelectric that
could fail — it draws it and measures the result against a value reached some other
way.
Across the library: 100 interrogated, 2 exercised only, 1 untouched, of 103. Read out of the gate's source by the gate's own two patterns — and the gate's last claim fails the build if that read disagrees with what it was handed while running.
Where it is called
Changing this generator changes every figure on this list. That is what makes the list worth publishing rather than keeping in a check script.
A photon with a momentum, and a collision that proves it
X-rays bouncing off electrons come back with a longer wavelength. How much longer depends on the angle they turned through, and on nothing else — not the incident wavelength, not the target material, not the intensity.
QuantumLight arrives in lumps, and brightness only changes how many
Shine dim blue light on a metal and electrons come out. Shine intense red light and none do, however long the wait. The frequency decides whether anything happens; the intensity decides only how much.