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Question
With the help of a suitable example and an equation, explain the term pair production.
Solution
Pair Production:
When a photon passes near a massive particle like an atomic nucleus, the photon disappears by creating an electron-positron pair. This process is called pair production. The energy of the photon should be equal to the sum of energy of electron and energy position. So a photon must have an energy of at least `2m_oc^2` to create an electron-positron pair. Where `m_o` is the rest mass of an electron.
To conserve momentum, the nucleus recoils with very small velocity. Pair production is also known as the materialization of radiant energy.
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What is 'Pair production'?