A positive charge moves with speed v parallel to a uniform magnetic fi…

Question

A positive charge moves with speed v parallel to a uniform magnetic field B. The magnetic force on the charge is:

Accepted Answer

C. Zero, as v is parallel to B

1. Magnetic force magnitude: $F = qvB\sin	heta$.
2. When $\mathbf{v}$ is parallel to $\mathbf{B}$, the angle $	heta = 0^\circ$.
3. Then $\sin 0^\circ = 0$, so $F = 0$.
4. The vector product vanishes when velocity and field are parallel.
_Source: syllabus Physics Ch 4 "Moving Charges and Magnetism", p.135_

Answer

qvB, perpendicular to v

Answer

qvB, directed along v

Answer

Maximum, along B

A positive charge moves with speed v parallel to a uniform magnetic field B. The magnetic force on the charge is:

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