Question

1. if the direction of current flow in an electromagnet is suddenly reversed, what will happen to the magnet?

the magnetic field will double in intensity.

the magnet will reverse polarity.

the magnetic field will decrease in intensity.

nothing will happen.

Explanation:

Understand electromagnetism principles

Using the Electromagnetism knowledge point
An electromagnet produces a magnetic field when electric current flows through its wire coil. The strength of this magnetic field depends on the current magnitude and the number of turns, while its direction is determined by the direction of the current.

Apply the left-hand rule

Using the Left-hand rule for electromagnets knowledge point
The left-hand rule (or right-hand rule, depending on conventional current vs. electron flow) relates the direction of current around the coil to the magnetic north pole. Reversing the current direction reverses the direction of the magnetic field lines, which causes the magnetic poles (north and south) to swap places.

Determine the physical outcome

Using the Electromagnetism knowledge point
Since the magnitude of the current remains unchanged, the intensity of the magnetic field does not increase or decrease. The only change is the direction of the field, meaning the magnet will reverse its polarity.

Answer:

• The magnetic field will double in intensity.
• The magnet will reverse polarity. (Correct answer)
• The magnetic field will decrease in intensity.
• Nothing will happen.