A magnetic field is the space around a magnetic material that is active, and attracts ferro-magnetic metals. These include iron, cobalt, steel, nickel and manganese, but there are others. We describe two simple experiments to plot a magnetic field around a magnet. You will find this information useful if it pops up in a school examination.
First of Two Experiments to Plot a Magnetic Field
For this experiment you will need the following materials:
- A sheet of clean white paper
- A pencil or thin marker pen
- General purpose adhesive tape
- A small supply of iron filings
- A bar magnet with straight sides
Place the sheet of clean white paper on a level surface, and secure it with the adhesive tape. Then position the magnet with the broad side facing down, and draw a line around it with the pencil, or thin marker pen.
Now gently sprinkle the iron filings over the paper around the magnet. Then gently tap the paper and observe what happens next. You should see the iron filings rearrange themselves as they settle on the magnetic field lines.
How to Plot a Magnetic Field with a Compass
You will need the following materials for our second experiment to plot a magnetic field on a piece of paper:
- A second sheet of clean white paper
- A pencil or thin marker pen
- General purpose adhesive tape
- A plotting compass showing magnetic north
- A bar magnet with straight sides
Place the sheet of clean white paper on a level surface, and secure it with the adhesive tape nearby the first one. Then position the magnet with broad side facing down, and draw a line around it with the pencil, or thin marker pen.
Now, make a small mark on the paper next to a corner of the magnet. Position the compass next to that mark, so one end of the needle points to it. Make a second dot opposite the other end of the needle. Remove the compass and connect the two dots with a straight line.
Continue the process beginning at the second dot, until you have chain of lines surrounding the magnet from one end to the other. This completes one magnetic field line. Repeat the procedure several ties to create a map of the magnetic field. Compare the results from the two experiments. What did you learn from this experiment?
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Video Share Link (Iron Filings): https://youtu.be/Xy6H0mr3KXw