Magnetic Effects of Electric Current: common misconceptions

If your child says… “Invisible threads pull the needle.”

Ask together

Would erasing the drawn lines stop the magnet turning a compass?

What’s true

The lines are drawings, with closer spacing showing stronger fields.

If your child says… “The field follows the wire.”

Ask together

Do your curled fingers follow the wire or circle it?

What’s true

The field circles the wire, strengthens with current, and weakens with distance.

If your child says… “Opposite sides cancel each other.”

Ask together

Do the two centre symbols show matching or opposite field directions?

What’s true

Each part of the loop produces a field pointing the same way at its centre.

If your child says… “The hollow centre has no field.”

Ask together

Where do the neighbouring turns' fields add together?

What’s true

A solenoid's hollow centre contains a magnetic field when current flows.

If your child says… “Opposite forces always cancel.”

Ask together

Do these opposite forces act along the same line?

What’s true

These opposite forces act along different lines, so they turn the coil.

If your child says… “A still magnet keeps current flowing.”

Ask together

What does the meter show while the magnet rests inside?

What’s true

A magnet resting inside a stationary coil induces no current because the field stays unchanged.

If your child says… “Earth carries the working current.”

Ask together

Which wire provides the normal return path: neutral or earth?

What’s true

Earth connects the casing to ground for fault current and normally carries no current.

If your child says… “Overloading means current stops.”

Ask together

Does current stop when appliances overload the circuit, or when the fuse breaks the circuit?

What’s true

Overloading increases current before protection breaks the circuit.