Module 06 — Heat and Particles · quiz worth 14 pts
The symbols overlap, so decide whether the question is about photon energy, light wavelength, or matter wavelength.
Use E = hf.
Use c = fλ.
Use λ = h/p, with p = mv when speeds are nonrelativistic.
NIST's constants reference is useful for checking h and c. It supplies reference values, not an explanation of wave-particle evidence.
A problem gives a photon's frequency and asks for energy. What is the first equation?
E = hf.
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Protons and neutrons are composite particles made from quarks and gluons. In the course's valence-quark model, a proton has two up quarks and one down quark (uud); a neutron has one up and two down quarks (udd). Gluons mediate the strong interaction that binds quarks. Electrons are elementary leptons in the Standard Model, not bundles of quarks.
Each particle has a corresponding antiparticle with the same invariant mass and opposite relevant charges. An electron and positron can annihilate into photons while conserving total energy, momentum, charge, and other required quantities. Rest energy is E = mc². The energy is transformed, not destroyed.
Interference and diffraction are wave behaviors. Light produces them, and electrons can also form interference patterns when an experiment preserves their quantum coherence. The photoelectric effect shows that light exchanges energy in localized quanta called photons. A complete quantum account is not a choice between a tiny classical ball and a classical water wave.
Name what the experiment records.
Interference or diffraction shows wave behavior.
The photoelectric effect supports photons with E = hf.
Neither a classical ball nor a classical water wave explains every result.
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E in joules, frequency f in hertz, and Planck's constant h = 6.626 × 10⁻³⁴ J·s.
For light in vacuum, c = 2.998 × 10⁸ m/s.
For nonrelativistic motion, momentum p = mv in kg·m/s.
m is invariant or rest mass. A photon has m = 0 but nonzero energy and momentum.
Energy points to E = hf. Wavelength and frequency point to c = fλ. Matter wavelength points to λ = h/p.
Convert nanometers to meters and electronvolts to joules only when the equation and requested unit require it.
Higher frequency means greater photon energy and shorter wavelength in vacuum.
Macroscopic momentum makes de Broglie wavelength extremely small. Electron-scale momentum can make it measurable.
Cover the equations that do not contain your target.
Match the given and target symbols.
Use meters, seconds, kilograms, and joules unless the problem provides a compatible alternative.
Higher f means higher E and shorter λ for light in vacuum.
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Find its energy.
E = 3.31 × 10⁻¹⁹ J.
Find its de Broglie wavelength.
λ ≈ 1.0 × 10⁻³⁴ m, far too small for ordinary diffraction measurements.
What minimum total photon energy can result if the pair annihilates from rest?
Etotal = 1.64 × 10⁻¹³ J, shared by the photons while momentum is conserved.
A photon has no invariant rest mass, but it carries E = hf and momentum p = E/c.
Cosmic rays are mostly high-energy charged particles. Radio through gamma rays are electromagnetic radiation.
Quantum objects do not alternate between a classical wave and classical particle. Different experiments reveal different quantum statistics.
Two or more photons may be required by the initial state; energy conservation alone is not the whole check.
Write the relation, insert SI values, then test whether the scale makes physical sense.
