A beam of electrons is moving with constant velocity in a region having electric and magnetic fields of strength $20\;V{m^{ - 1}}$ and $0.5 T$ at right angles to the direction of motion of the electrons. What is the velocity of the electrons............ $m{s^{ - 1}}$
  • A$20$ 
  • B$40$ 
  • C$8$ 
  • D$5.5$ 
AIPMT 1996, Easy
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