The following experiment was performed by a group of students as a
practical investigation into electromagnets.
Method
The apparatus was set up as shown in the diagram.
An iron nail was used as the core of the electromagnet.
Insulated wire was carefully wrapped around the
nail to form the electromagnet coil.
How the strength of the electromagnet changed
was found by comparing how many paperclips the electromagnet could
pick up.
The paperclips were attached to form a chain
of varying weights so that the strength of the electromagnet could
be fairly assessed.
The number of turns of wire was kept constant
while the current was varied and then the current was kept constant
while the number of turns was varied.
Results
Current/A passing through the
coil
|
Number of Turns of wire on
the electromagnet
|
Number of paperclips picked
up by the electromagnet
|
0
|
50
|
0
|
0.5
|
50
|
1
|
1.0
|
50
|
5
|
1.5
|
50
|
13
|
2.0
|
50
|
21
|
2.5
|
50
|
30
|
3.0
|
50
|
36
|
3.5
|
50
|
45
|
Current/A passing through the
coil
|
Number of Turns of wire on
the electromagnet
|
Number of paperclips picked
up by the electromagnet
|
3.0
|
10
|
6
|
3.0
|
20
|
12
|
3.0
|
30
|
19
|
3.0
|
40
|
26
|
3.0
|
50
|
32
|
3.0
|
60
|
39
|
3.0
|
70
|
43
|
3.0
|
80
|
50
|
Plot graphs to show how the number of paperclips picked up by the electromagnet
varied with
- the current flowing through the electromagnet
- the number of turns of wire of the electromagnet
Use your graphs to describe any pattern or trend that you observe.
|