The rest mass energy of an electron is:
Correct answer: C. 0.511 Mev
- A. 9.11 x 10^-31 J
- B. 6.7 Mev
- C. 0.511 Mev
- D. 1.67 x 10^-27 J
Explanation
The electron rest mass (symbol: me) is the mass of a stationary electron, also known as the invariant mass of the electron. It is one of the fundamental constants of physics. It has a value of about 9.109×10−31 kilograms or about 5.486×10−4 daltons, equivalent to an energy of about 8.187×10−14 joules or about 0.5110 MeV.
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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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