Magnetic fields are invisible to the naked eye, so viewing and measuring them is impossible without additional materials or tools. We’ll look at magnetic fields one way in the pre-lab, and another way during this lab. Inspiration for this lab comes from this paper (Measurement of the magnetic field of small magnets with a smartphone).

Pre-Lab

Materials

Iron Filings
Bar Magnet
Paper
Pencil
Science Notebook

Directions

1. Put the Bar Magnet on your lab table.
2. Place the piece of paper over the magnet
3. Slowly shake iron filings over the piece of paper. Imagine you’re trying to lightly sprinkle sugar over strawberries.
4. Tap the piece of paper gently, twice.
5. Draw what you see in your lab notebook.

Lab

Materials

Smart phone with magnetometer
Ruler
Paper
Small Magnet

Directions

1. Draw a line down the center of the paper. 
2. Place the magnet under the paper, on the line.
3. Begin logging data from internal magnetometer using SPARKvue app
4. Move the phone around the paper until the magnetometer reading peaks. Mark that on the paper.
5. Move the smartphone 1cm away from your body.
6. Record the magnetometer reading.
7. Repeat steps 5 and 6 20 times.
8. Plot the data.