Topic 12 & 13 Magnetism, motor effect & EM induction Flashcards
1 What are the two ends of a bar magnet called?
north-seeking pole and south-seeking pole, or just north pole and south pole
2 Name two magnetic materials.
any two from iron, cobalt, nickel, steel
3 What happens if you arrange two magnets with their north poles close to each other?
They repel each other.
4 How can you arrange two magnets so they attract each other?
put opposite poles close to each other/put a north pole near a south pole
5 What is a magnetic field?
the space around a magnet which affects magnetic materials
6 How can you find the shape of a magnetic field?
use iron filings or plotting compasses
7 Name two electrical devices that use magnets.
any two from motors, loudspeakers, generators
8 Why do compasses point north?
The Earth has a magnetic field.
9 Describe the shape of the Earth?s magnetic field.
similar to the field of a bar magnet
10 Why are compass needles weighted at one end?
In most places the Earth’s magnetic field is not parallel to the surface.
11 Which part of the Earth is responsible for the Earth?s magnetic field?
outer core
12 What is the difference between the Earth?s north magnetic pole and its North Pole?
The Earth spins around an axis through the North Pole; the north magnetic pole is where compasses point to.
13 What is an induced magnet?
something that is a magnet only because it is in the magnetic field of another magnet
14 Name two materials that an induced magnet could be made from.
any two from iron, cobalt, nickel, steel
15 You are using plotting compasses to find the shape of the magnetic field of a bar magnet. Which way does the needle point?
away from the north pole/towards the south pole
16 How does a magnetic field diagram show where the field is strongest?
strongest where the lines are closest together
17 What is a uniform magnetic field?
a field with the same strength and direction everywhere
18 How can you produce a uniform magnetic field?
using two flat magnets
19 What is the shape of the magnetic field around a wire with a current flowing through it?
circular around the wire
20 What is an electromagnet?
a magnet made when current flows through a coil of wire