Sub-topic 1
2026 · National Semifinal
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Threshold photon energy for electron-positron pair production
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Sub-topic 2
2026 · National Semifinal
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Compton wavelength shift at a given scattering angle
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Sub-topic 3
2025 · National Semifinal
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Rate of photons striking a surface from a laser's power and wavelength
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Sub-topic 4
2026 · National Quarterfinal
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Wien's displacement law: peak wavelength of blackbody radiation
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Sub-topic 5
2026 · National Quarterfinal
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De broglie wavelength of an electron from its kinetic energy
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Sub-topic 6
2026 · National One-Eighth
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Linear momentum of a photon from its wavelength
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Sub-topic 7
2025 · National Quarterfinal
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X-ray photon energy from characteristic wavelength
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Sub-topic 8
2024 · National One-Eighth
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Photon energy from its frequency, expressed in electron volts
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Sub-topic 9
2022 · National Final
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Wien's displacement law: peak frequency of blackbody radiation
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Sub-topic 10
2025 · National Final
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Compton wavelength of the deuteron
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Sub-topic 11
2026 · National One-Eighth
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What determines the upper frequency bound of the electromagnetic spectrum (true/false)
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Sub-topic 12
2026 · National One-Eighth
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Riddle: spontaneous emission (photon emission not triggered by incoming photons)
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Sub-topic 13
2013 · National Preliminary
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J.j. thomson's experiment and the discovery of the electron (true/false)
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Sub-topic 14
2013 · National Preliminary
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Ranking electromagnetic spectrum regions by increasing energy
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Sub-topic 15
2013 · National Preliminary
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Ranking electromagnetic spectrum regions by increasing wavelength
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Sub-topic 16
2013 · National Semifinal
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Number of photons per second from a laser's power and photon frequency
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Sub-topic 17
2013 · National Semifinal
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Laser power from photon frequency and photon emission rate
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Sub-topic 18
2013 · National Semifinal
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Photon frequency from a laser's power and photon emission rate
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Sub-topic 19
2018 · National Preliminary
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Shortest (cutoff) x-ray wavelength from the accelerating voltage of an x-ray tube
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Sub-topic 20
2020 · National Preliminary
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Number of photons per second from a co2 laser's power and wavelength
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