In order to produce pair production the minimum energy of photon required is:
Correct answer: B. 1.02 MeV
- A. 1.02 KeV
- B. 1.02 MeV
- C. 10.2 KeV
- D. 1.00 MeV
Explanation
Pair production is a process where a photon is converted into an electron-positron pair. For this to occur, the photon must have a minimum energy equal to twice the rest mass energy of an electron, which is approximately 1.02 MeV. This is because the rest mass energy of an electron (or positron) is about 0.511 MeV, and two such particles are created. Therefore, 1.02 MeV is the minimum necessary energy for pair production. The options 1.02 KeV and 10.2 KeV are far too low, as they are measured in KeV (kilo-electron volts) rather than MeV (mega-electron volts). Option 1.00 MeV is close but does not meet the required threshold.
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Classical physics cannot explain blackbody radiation and related observations, leading to Planck’s quantum theory, in which energy is emitted or absorbed in discrete packets. Photons provide the particle model of light, with energy and momentum linked to frequency and wavelength, including the photoelectric effect and its threshold frequency.
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