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JEE Main202524 Jan 2025Evening ShiftPhysicsMagnetic Effects of CurrentActual

Given below are two statements. One is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A) : A electron in a certain region of uniform magnetic field is moving with constant velocity in a straight line path. Reason (R): The magnetic field in that region is along the direction of velocity of the electron. In the light of the above statements, choose the correct answer from the options give

Options

  1. A(A) is true but (R) is false
  2. BBoth (A) and (R) are true but (R) is NOT the correct explanation of (A)
  3. CBoth ( A ) and ( R ) are true and ( R ) is the correct explanation of ( A )
  4. D(A) is false but (R) is true

Correct answer

C. Both ( A ) and ( R ) are true and ( R ) is the correct explanation of ( A )

Step-by-step solution

If the electron's velocity is along the direction of magnetic field then magnetic force on electron is zero and it will not accelerate.

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