Soft magnetic materials are hard to magnetise but stay magnets for longer periods
Answer
True
False
Question 2
Question
With a steady current in an electromagnet no e.m.f is needed because the magnetic field is not changing
Answer
True
False
Question 3
Question
To make an electromagnet stronger one can...
Answer
put more coils on the wire
run more electrical current through the wire
use an iron core
use a permanent magnet
Question 4
Question
When a magnet moves into a coil of wire, a voltage is induced and current flows...
What kind of current is this?
Answer
Direct Current (DC)
Alternating Current (AC)
Question 5
Question
What is electromagnetic induction?
Answer
When a magnet cuts through a conductor resulting in a flow of current
To start an alternating current of electricity using an electromagnet
Creating an electromagnet out of a metal
Question 6
Question
If there are more coils on the primary coil than on the secondary coil it is [blank_start]a step down[blank_end]
Answer
a step down
a step up
a transformer
Question 7
Question
A.C p.d is produced in the...
Answer
secondary coil
primary coil
Question 8
Question
The A.C in the [blank_start]primary coil[blank_end] produces [blank_start]an alternating[blank_end] magnetic field
Answer
primary coil
secondary coil
an alternating
a direct
Question 9
Question
([blank_start]p.d[blank_end] across [blank_start]primary coil[blank_end] (v) / ([blank_start]p.d[blank_end] across [blank_start]secondary coil[blank_end] (v)) = ([blank_start]number of turns[blank_end] on [blank_start]primary coil[blank_end] / [blank_start]number of turns[blank_end] on [blank_start]secondary coil[blank_end])
Answer
p.d
Amps
primary coil
secondary coil
p.d
Amps
secondary coil
primary coil
number of turns
e.m.f
primary coil
secondary coil
number of turns
e.m.f
secondary coil
primary coil
Question 10
Question
A long coil with many turns is called a [blank_start]solenoid[blank_end]
Answer
solenoid
Question 11
Question
Relays are used to break a circuit if the electrical current is too high
Answer
True
False
Question 12
Question
Why is iron a better core to use for an electromagnet?
Answer
steel is a hard metal and would become permanently magnetised
steel is a soft metal and would lose its magnetic ability to quickly