Electromagnetic Induction

Question 1

What is electromagnetic induction?

Answer 1

Thé création of a potential difference across a conductor which is experiencing a change in magnetic field

Question 2

How can you do electromagnetic induction?

Answer 2

By moving a magnet in a coil of wire or moving an electrical conductor in a magnetic field

Shifting the magnet from side to side creates a little blip of current

Question 3

What happens if you move the magnet in the opposite direction?

Answer 3

Thé potential difference / current will be reversed

Question 4

What happens if the polarity of the magnet is revered?

Answer 4

Thé potential difference / current will be reversed to

Question 5

What happens if you keep the magnet or the coil moving backwards and forwards?

Answer 5

You produce a potential difference that keeps swapping direction
This is how you produce an alternating current

Question 6

How can you create the same effect?

Answer 6

By turning a magnet end to end in a coil to create a current that lasts as long as you spin the magnet which is how generators work

Question 7

What happens as you turn the magnet?

Answer 7

Thé magnetic field through the coil changes- this change induces a potential difference which can make current flow in the wire

Question 8

What happens when you’ve turned a magnet through half a turn?

Answer 8

Thé direction of the magnetic field through the coil reverses when this happens the potential difference reversed so the current slows in the opposite direction around the coil of wire

Question 9

What happens if you keep turning the magnet in the same direction?

Answer 9

Thé potentia différence will keep on reversing every half turn and you’ll get an AC current

Question 10

How does a dynamo ( often used to power lights on bikes) work?

Answer 10

A cog wheel is positioned so it touches one of the wheels
As the wheel moves round it turns the cog which is attached to the magnet
This creates an AC current to power the lights