Exploring Electromagnetism

The fourth lab activity extends the detection of electromagnetic force to the study of solenoids. Students investigate how coiling the wire strengthens the magnetic field generated by the current carrying wire. Because solenoids are present in multiple FabNet Invention Kits, this lab activity is also a crucial experience in the instructional sequence.

Essential Question:

What are the properties of an electromagnet?

Materials

For this experiment, you will use the same materials as you used in the previous activity; a compass, 30cm piece of wire, and a 9V battery. 

Step 1

Begin by using the same piece of wire used in the previous activity. Make a small loop of wire, shown in the photo to the left.

Step 2

Place the loop of wire over the compass, just like in the previous activity. Connect the end of the wires up to the terminals of the battery. What do you observe? What happens if you change the orientation of the battery terminals?

Step 3

Now place the loop of wire under the compass, just like before in the previous activity. Repeat the same procedure of connecting the wires to the battery, and then changing the orientation of the battey terminals.

Step 4

Unwind the single loop and wrap the wire around the length of the compass several times. The wrap should be parallel with the North/South line on the compass. Leave enough length of wire on each side to connect up to the battery.

Step 5

Connect each end of the wire to the battery.

Solenoid_A4_09What do you observe?
How does this deflection compare to the deflection seen in previous experiments?

Step 6

Solenoid_A4_08

Finally, change the orientation of the wire connections to the battery.
What do you observe?

Animation