Topic 12 - Magnetism & The Motor Effect

Question 1

Uses of Permanent Magnets:

Answer 1

• Motor
• Speaker
• Transformer

Question 2

Uses of Temporary Magnets:

Answer 2

• Medical Devices (cobalt)
• Fridge Magnets
• Electromagnets

Question 3

Permanent Magnets:

Answer 3

• Magnetic properties without needing any external influence

Question 4

Temporary Magnets:

Answer 4

• Magnetic properties temporarily when placed in a magnetic field

Question 5

The use of compasses to show the shape of the Earth’s magnetic field:

Answer 5

• On a compass, north goes to the north pole because that is the earth geological south pole

Question 6

Explain how the behaviour of a magnetic compass is related to evidence that the core of the Earth must be magnetic

Answer 6

• The core of the Earth is primarily composed of iron and nickel

Question 7

What causes magnetic forces?

Answer 7

• Interactions between magnetic fields

Question 8

The Motor Effect

Answer 8

• When current acts on coil in a magnetic field, a force acts, and rotates the coil
• Split Ring Commutator changes current direction every half turn in the coil, so current keeps traveling in the same direction.