Magnetism Flashcards
Name 4 magnetic materials
Nickel
Cobalt
Iron
Steel
Steel is a magnetic alloy because it contains what?
Iron
Define Induced magnets
Magnetic materials that become magnets when in a magnetic field
Loses magnetism when you take it out of the magnetic field
Which direction do arrows on magnetic field lines point?
North to South
Define Magnetic field
The area around a magnet where other magnets or magnetic materials experience a force
Name the 2 poles of a magnet
North
South
How do you show the strength of a magnetic field?
Draw field lines closer together
Name the 4 rules of drawing magnetic field lines
Lines never cross
North to South
Continuous
Closer lines = stronger force
Where is a magnetic field strongest?
At the magnet’s poles
Uniform Field
When you place a north and south pole near each other, the magnetic field is the same strength everywhere between the poles
How can you use a plotting compass to show the direction of a magnetic field?
Put magnet of piece of paper and draw round it
Place compass on the paper near the magnet (needle will point in the direction of the field line at this position)
Mark the direction by drawing a dot at each end of the needle
Move compass so the tail end of the needle is where the tip of the needle was in the previous position and mark at the tip of the needle
Repeat this and join the marks with a curved line
Repeat everything at different points around the magnet to get several field lines
Geographical North Pole
Magnetic South Pole
Permanent Magnet
Always produces its own magnetic field (e.g. bar magnet)
Name 3 ways in which you can increase the strength of an electromagnet
Increase more number of turns to the coil.
Increase in current or voltage.
What do magnetic materials do when close to a permanent magnet?
Always attract
Become induced magnets
