JEE Mains · Physics · STD 12 - 4. Moving charges and magnetism
A charge particle moving in magnetic field \(B\), has the components of velocity along \(B\) as well as perpendicular to \(B\). The path of the charge particle will be
- A helical path with the axis perpendicular to the direction of magnetic field \(B\)
- B straight along the direction of magnetic field \(B\)
- C helical path with the axis along magnetic field \(B\)
- D circular path
Answer & Solution
Correct Answer
(C) helical path with the axis along magnetic field \(B\)
Step-by-step Solution
Detailed explanation
Due to component \(v_1\), magnetic force \(F = qv _1 B \sin \theta=0\) So \(v _1\) remains unchanged but due to component \(v_2\) magnetic force act towards centre i.e. moving it circular. So path is helical with the axis parallel to magnetic field \(B\).
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