Electromagnets and Electromagnetic Induction _ GCSE Physics

The video tutorial explains the formation of magnetic fields around wires and how coiling a wire can create an electromagnet. It highlights the practical uses of electromagnets, such as in scrap yards. The concept of electromagnetic induction is introduced, explaining how a changing magnetic field can produce a potential difference, leading to alternating current. The video also describes how generators work by using a spinning magnet within a coil of wire to produce electricity for homes.

What happens to the magnetic field when a wire is coiled?

• It changes direction.

• It becomes weaker.

• It disappears.

• It resembles a bar magnet.

Why are electromagnets useful in scrap yards?

• They are always on.

• They are very small.

• They do not require electricity.

• They can be turned off to release objects.

What is electromagnetic induction?

• The process of cooling a magnet with a wire.

• The process of heating a wire with electricity.

• The process of generating a current with a magnetic field.

• The process of creating a magnetic field with a current.

How is an alternating current produced in a wire?

• By keeping the wire stationary in a magnetic field.

• By moving the wire in a constant direction.

• By heating the wire.

• By moving the wire back and forth in a magnetic field.

How do generators produce an alternating current?

• By using a battery.

• By using a stationary magnet and wire.

• By spinning a magnet within a coil of wire.

• By heating the wire.