Do now!

Can you continue with the ‘Draw the sentences’ from

last lesson?

This is to be FINISHED FOR HOMEWORK. Due

next Friday 16th September.

Today’s lesson

• Plotting magnetic fields

• Electromagnetic induction

Plotting magnetic fields

Can you gather around

Mr Porter?

Quietly and sensibly

Plotting magnetic fields

Magnetic field lines

The closer the field lines are, the stronger the magnetic force felt

The arrows show the direction a compass needle would point at that point in the field.

Field around a bar magnet

Electromagnetic induction

• Can you carefully wind your wire around the cardboard tube?

Electromagnetic induction

• Put your coil in this circuit. The multimeter should be on the μA scale.

μA

Electromagnetic induction

• MOVE a magnet in and out of the coil. Watch the meter!

μA

Electromagnetic induction

If a magnet is moved inside a coil an electric current is induced (produced)

Electromagnetic induction

If a magnet is moved inside a coil an electric current is induced (produced)

COPY this please!

Electromagnetic induction

A electric current is induced because the magnetic field around the coil is changing (the coil ‘cuts through’ the lines of field).

COPY this please!

Gather round

• http://phet.colorado.edu/sims/faraday/generator_en.jnlp

Generator/dynamo

A generator works by rotating a coil in a magnetic field (or rotating a magnet in a coil). A slip-ring commutator produces alternating current (a.c.)

Can you stick this in please?

COPY this please!

Let’s try some questions!Pages 215 and 219.