Answer: zero.
- A zero
- B maximum
- C attractive
- D repulsive
Correct answer: A. zero
Explanation: A magnetic force acts only on moving charges; a stationary charge feels none.
The magnetic field around a long straight current-carrying wire forms concentric circles, with direction given by the right-hand rule (point thumb along I, fingers curl in the direction of B).
Concept context
Magnetic force on moving charges and currents, the Biot-Savart law, Ampere's law, and the cyclotron - how electric currents create and respond to magnetic fields.