WorksheetsElectromagnets
Total questions: 15
Worksheet time: 17mins
Name
Class
Date
1.
The strength of an electromagnet can be affected by
a)
changing the current in the wire
b)
changing the number of loops in the solenoid
c)
changing the size of the iron core
d)
all of the above
2.
Bob made an electromagnet but it was very weak. How can he make it stronger?
a)
take away a d-cell
b)
wrap the wire loosely
c)
use thicker wire
d)
use less turns
3.
What component becomes a temporary magnet when electricity is flowing through the circuit?
a)
d -cell
b)
wire coil
c)
switch
d)
core
4.
Samuel Morse, the inventor of the telegraph had a problem. How can he increase the strength of the electromagnet in his telegraph?
a)
use thinner wire
b)
add more d-cells
c)
add a switch
d)
wind fewer wraps of wire around core
5.
This is a picture of a simple electromagnet. How can the electromagnet be made stronger?
a)
Add more coils of wire to the nail.
b)
Use a smaller battery.
c)
Reverse the poles of the magnet.
d)
Remove all the coils and the nail.
6.
In order for an electromagnet to be formed, an __________ current must pass through a coil of __________ wrapped around an ________ core.
a)
wire, iron, electric
b)
electric, wire, iron
c)
iron, electric, wire
d)
excited, hair, apple
7.
Any material that attracts iron or materials containing iron is a(n)
a)
A. electric generator
b)
B. solenoid
c)
C. magnet
d)
D. magnetic force
8.
How do electromagnets differ from regular magnets?
a)
A. They can be turned off and on
b)
B. Their polarity can be reversed
c)
C. Their strength can be changed
d)
D. All of the above
9.
A compass needle responds to a magnetic field, because the compass needle is a
a)
A. generator.
b)
B. motor.
c)
C. magnet.
d)
D. transformer.
10.
Where does a magnetic field occur in relation to an electrified wire?
a)
At either end, but not in the middle
b)
Only the side closest to source
c)
Around the entire length of wire
d)
Only the side furthest from source
11.
Why are paper clips attracted to magnets?
a)
They contain silver.
b)
They contain aluminum
c)
They contain tin.
d)
They contain iron.
12.
An electromagnet is made of ...
a)
An iron bar
b)
An iron core & wire
c)
Wire
d)
An iron core & electric circuit
13.
Where is the magnetic force the strongest on a magnet?
a)
at the poles
b)
in the middle
c)
above the magnet
d)
below the magnet
14.
A student made an electromagnet by wrapping copper wire around an iron nail. The student then connected each end of the electromagnet to the opposite terminals of a battery. The electromagnet will best function as a magnet as long as...?
a)
electric current flows through the nail.
b)
electrical energy is transformed into mechanical energy.
c)
electric current flows through the wire.
d)
electrical energy is transformed into potential energy.
15.
In an electromagnet, the part of the core that is connected to the positive charge of the battery becomes the ___________ pole of the electromagnet.
a)
south
b)
north
c)
can not be determined
100 %
