Which change does NOT increase the strength of an electromagnet?

Reversing the direction of the current

Electromagnetic induction generates a voltage in a coil when:

The magnetic flux through the coil changes

It magnetises and demagnetises easily, so the magnetism switches off when the current stops

Opposes the change that produces it

Only AC continuously changes the flux, which is needed to induce a secondary voltage

When it is at right angles to the field

12questions. Pick an answer and you'll see why right away.

What happens when the north poles of two magnets are brought close together?
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Which change does NOT increase the strength of an electromagnet?
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Electromagnetic induction generates a voltage in a coil when:
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