JEE Mains · Physics · STD 12 - 4. Moving charges and magnetism
\(1\,\mu\)C charge moving with velocity \(\vec{v} = \left(\hat{i} - 2\hat{j} + 3\hat{k}\right)\) m/s in the region of magnetic field \(\vec{B} = \left(2\hat{i} + 3\hat{j} - 5\hat{k}\right)\) T. The magnitude of force acting on it is \(\sqrt{\alpha} \times 10^{-6}\) N. The value of \(\alpha\) is _______.
- A 165
- B 168
- C 170
- D 171
Answer & Solution
Correct Answer
(D) 171
Step-by-step Solution
Detailed explanation
The magnetic force acting on a moving charge is given by \(\vec{F} = q(\vec{v} \times \vec{B})\). Given: \(q = 1 \, \mu\text{C} = 10^{-6} \text{ C}\) \(\vec{v} = \hat{i} - 2\hat{j} + 3\hat{k}\) \(\vec{B} = 2\hat{i} + 3\hat{j} - 5\hat{k}\) Calculating the cross product…
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