Answer: bar magnet.
- A bar magnet
- B capacitor
- C resistor
- D battery
Correct answer: A. bar magnet
Explanation: A solenoid produces a field like that of a bar magnet, with a north and a south pole.
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.