JEE Mains · Physics · STD 12 - 4. Moving charges and magnetism
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 :
- A (A) is true but (R) is false
- B Both (A) and (R) are true but (R) is NOT the correct explanation of (A)
- C Both \((\mathbf{A})\) and \((\mathbf{R})\) are true and \((\mathbf{R})\) is the correct explanation of \((\mathbf{A})\)
- D (A) is false but (R) is true
Answer & Solution
Correct Answer
(C) Both \((\mathbf{A})\) and \((\mathbf{R})\) are true and \((\mathbf{R})\) is the correct explanation of \((\mathbf{A})\)
Step-by-step Solution
Detailed explanation
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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