JEE Mains · Physics · STD 12 - 4. Moving charges and magnetism
The charged particle moving in a uniform magnetic field of \((3\hat{i} + 2\hat{j})\) T has an acceleration \(\left(4\hat{i} - \dfrac{x}{2}\hat{j}\right)\) m/s\(^2\). The value of \(x\) is __________.
- A 12
- B 24
- C 36
- D 48
Answer & Solution
Correct Answer
(A) 12
Step-by-step Solution
Detailed explanation
The magnetic force on a moving charged particle is given by \(\vec{F} = q(\vec{v} \times \vec{B})\). Since the acceleration \(\vec{a}\) is in the direction of the magnetic force, it must be perpendicular to the magnetic field \(\vec{B}\). Therefore, the dot product of…
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