What is a magnetic field?
The area around a magnet where the effects around a magnet can be detected
How do you make a temporary magnet?
By stroking a permanent magnet on an item that is magnetic (e.g. iron or steel).
How is an electromagnet made?
An electromagnet is made by wrapping a wire around a magnetic material and passing an electric current through it
Complete this sentence:
Like poles ____, opposite poles ____
Like poles repel, opposite poles attract
What 3 factors affect the strength of an electromagnet?
- Number of turns of coils
- The material of the core
- The amount of current passing through the coil
Name a suitable material for the core of an electromagnet?
Iron
What is the difference between a permanent magnet and a temporary magent?
A permanent magnet cannnot turn on and off its magnetism but a temporary magnet can be turned on and off
What piece of apparatus could be used to show the direction of the field lines?
A compass
Name 3 magnetic metals
Iron, nickel and steel
From a point on the equator of the Earth, in which direction do the Earth’s magnetic field lines point?
Toward geographic north
Which statement is true about the Earth’s magnetic field. Write the number.
- The Earth’s magnetic field occurs only at poles.
- The Earth’s magnetic field occurs only at the equator.
3.The Earth’s magnetic field occurs all around the Earth.
- The Earth’s magnetic field occurs at certain times.
3
Why does the earth have a magnetic field?
The earth’s core is made from iron and nickel, which are magnetic materials
Which of these is stronger. Write the number
- The Earth’s magnetic field.
- The strength of the magnetic field 1 cm from the end of a bar magnet.
2
What is one material that you can use to test an electromagnet?
Steel paperclips
State the part of the Earth that the Earth’s magnetic field comes from.
The core
True or False
- The magnetic field around a bar magnet is uniform
False
Describe one use of electromagnets
- MRI scanner
- Fire alarms
- Toaster
- Electric bell
Which statements are true about the Earth’s magnetic field? Write the numbers.
- The Earth’s magnetic poles have not always been in the same positions.
- The Earth’s magnetic poles are exactly the same as the geographic poles.
- The Earth’s magnetic poles are similar to the poles of a bar magnet.
1 and 3
When doing an experiment to create an electromagnet, what are 3 things you should keep the same to make a fair test?
- Size and materialof paperclips
- Same current in coil
- Same size and material in the core
Explain the difference between magnetic and magnetised
Magnetic describes a material that is attracted to a magnet. Magnetised means the process of turning a material into a magnet.
