Below is a picture of an electromagnet made by wrapping a wire around an iron nail and connecting it to a battery. The electromagnet can be turned off by disconnecting it from the battery. A teacher helps students perform 2 experiments to test the variables that affect the electromagnet’s magnetic strength. Experiment 1The students build an electromagnet using a 4.5 volt battery connected to an iron nail with coils wrapped around it. They change the number of coils around the nail and record how many paperclips the electromagnet can pick up each time. The results are shown in the table below.Experiment 2In the second experiment, the students keep the same number of coils around the nail and records how many paperclips the electromagnet can pick up using different batterie
s. The results are shown in the table below.
Experiment 1:
Number of Coils: Number of Paperclips Picked Up:
10 3
20 5
30 8
40 12
50 15
Experiment 2:
Battery Voltage: Number of Paperclips Picked Up:
3V 2
4.5V 5
6V 9
9V 14
12V 18
In Experiment 1, the students varied the number of coils around the iron nail while keeping the battery voltage constant at 4.5 volts. They observed that as the number of coils increased, the magnetic strength of the electromagnet increased. This was evident from the increased number of paperclips the electromagnet was able to pick up.
In Experiment 2, the students kept the number of coils constant while varying the battery voltage. They found that as the battery voltage increased, the magnetic strength of the electromagnet also increased. This was evident from the increased number of paperclips the electromagnet was able to pick up.
These experiments show that the magnetic strength of an electromagnet can be influenced by the number of coils and the battery voltage. Increasing either of these variables results in a stronger electromagnet.