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MHT CET202122 Sep 2021Evening ShiftPhysicsElectrostaticsActual

An electron of mass ' m ' and charge ' q ' is accelerated from rest in a uniform electric field of strength ' E '. The velocity acquired by the electron when it travels a distance ' L ' is

Options

  1. A2 q E mL
  2. B2 E m q L
  3. C2 qEL m
  4. DqE mL

Correct answer

C. 2 qEL m

Step-by-step solution

Force on the electron F = qE Work done by the force W = qEL Work done is equal to gain in kinetic energy aligned & 1 2 mv ^2= qEL & v = 2 qEL m aligned

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