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The rest energy of an electron is....

The rest energy of an electron is.

A

`510 KeV`

B

`931 KeV`

C

`510 MeV`

D

`931 MeV`

Text Solution

Verified by Experts

The correct Answer is:
A
(a) Rest energy of an electron `= m_e c^2`
Here, `m_e = 9.1 xx 10^-31 kg` and `c =` velocity of light
`:.` Rest energy `= 9.1 xx 10^-31 xx (3 xx 10^8)^2` Joule
`=(9.1 xx 10^-31 xx (3 xx 10^8)^2)/(1.6 xx 10^-19) eV = 510 keV`.
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Knowledge Check

  • The energy of an electron

    A
    is greater in outer orbits
    B
    is greater in inner orbits than in outer orbits
    C
    is always the same which ever are the orbit
    D
    decreases as the quantum number increases

  • What should be the rest energy of an electron ?

    A
    510 KeV
    B
    931 KeV
    C
    510 MeV
    D
    931 MeV

  • Equivalent energy of mass equal to 1 amu is…A… and rest energy of an electron is …B… Here A and B refer to

    A
    `913 keV, 10 MeV`
    B
    `931 eV, 931 MeV`
    C
    `931.5 MeV, 510 keV`
    D
    `931 MeV, 931 KeV`

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