electicity and magnetism Flashcards
metal will only flow in what?
a complete circuit
if there is a break what will happen?
a current wont flow
why wont it flow if it breaks?
because only metals will allow charge(electrons) through them.
metals are a conductor of what?
electricity
what is a permanent magnet?
This means that its magnetism is there all the time and cannot be turned on or off. A bar magnet has two magnetic pole
What do two poles of the same type do when they are brought close together?
they repel
What do two unlike poles do when they are brought close together?
they attract
The arrow on magnetic field lines shows them flowing in which direction?
from north to south
Where are the field lines most concentrated around a bar magnet?
both poles
How can we increase the strength of an electromagnet?
add an iron core
What is one difference between electromagnets and bar magnets?
Electromagnets need electricity but bar magnets do not
What can we use to find the shape of a magnetic field?
a compass
what does not usually use an electromagnet?
a compass
What are all substances made from?
atoms
What happens to an atom if it gains an electron?
it becomes negative
