Magnetism

Question 1

magnetically hard materials

Answer 1

are magnetic for a very long time

Question 2

magnetically soft materials

Answer 2

can be demagnetised

Question 3

magnetic materials

Answer 3

iron nickel cobalt alloys

Question 4

how find magnetic field lines

Answer 4

place a compass at different points on a magnet. Mark down where the arrow ends up pointing and draw an arrow start where the mark is and place the compass there. repeat the process

Question 5

why do you need an electric current to make an electromagnet

Answer 5

a conductor with an electric current has a magnetic field

Question 6

How make electromagnet

Answer 6

coil a wire connected to a power source over an iron nail
turn on the power source

Question 7

uses of electromagnets

Answer 7

scrapyard cranes, maglev trains, door locks

Question 8

RHG rule

Answer 8

used to find direction of magnetic force on a positive moving charge

Question 9

what is a relay circuit

Answer 9

a relay circuit is consisted of two circuits, a primary and secondary circuit. the primary circuit has a low current flowing through it to power an electromagnet which will attract an armature and complete the second circuit which has a higher electrical current. this is done to protect the user from a circuit overload when the current is too high