If the electron's velocity is along the direction of magnetic field then magnetic force on electron is zero and it will not accelerate.
JEE Main 2025 — Physics Electromagnetism
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 given below :
Held on 24 Jan 2025 · Verified 6 Jul 2026.
(A) is true but (R) is false
Both (A) and (R) are true but (R) is NOT the correct explanation of (A)
Both (A) and (R) are true and (R) is the correct explanation of (A)
(A) is false but (R) is true
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