MCQ
The mass of the electron varies with
  • A
    The size of the cathode ray tube
  • B
    The variation of $‘g’$
  • Velocity
  • D
    Size of the electron

Answer

Correct option: C.
Velocity
c
(c)Mass is basically a constant term for any physical application at low velocity. But in accordance with Einstein’s theory of relativity, at higher speeds the mass of the particle change according to formula
$m = \frac{{{m_0}}}{{\sqrt {1 - ({v^2}/{c^2})} }}$

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