How to Experiment With Magnetic Shielding
Depending on how permeable they are, certain other materials, like air and cardboard, can also allow magnetic field lines to pass through. Test several materials to observe which ones work as magnetic shields and gather magnetic lines of force, and which ones permit magnetic lines of force to flow through. When neighboring items, such as cardiac pacemakers or other delicate bits of electronic or medical equipment, that may be subject to magnetic interference are present, magnetic shielding is crucial. Additionally, it becomes important if neighboring low frequency external magnetic fields must be protected from the magnetic field or fringe field from the MRI magnet. In general, the area surrounding the MR magnet requires it to be shielded from magnetic and fringe forces.
Tools and Resources
Three doughnut-shaped ceramic magnets (rectangular magnets will also work)
Two cardboard pieces, each measuring approximately 2 by 2 3/4 inches (5 x 7 centimeters)
Two pencils, each at least 2 3/4 in (7 cm) long
Six to eight paper clips
Plastic straws, craft sticks made of wood, or any nonmetallic object
An iron butter knife
Glue with a hot glue gun (alternatively, you can use rubber bands)
- Create a sandwich of cardboard and pencil first: By aligning the pencils perpendicular to one another and near to the cardboard’s opposing sides, you can adhere the pencils with one cardboard piece.
- Create a sandwich of cardboard, pencils, and a second cardboard piece by adhering it to the first two.
- With the aid of hot glue, affix one of the magnets to a cardboard piece on top. Put the magnet in the middle, next to an edge.
- To maintain their position by magnetic attraction, attach two additional magnets over the first magnet. Never glue them!
Doing and Observing
- With the magnets on top, hold your shielding sandwich. One at a time, lift the paper clips to the bottom surface and observe what happens. The magnet should draw the paper clips, which will dangle from the bottom of the cardboard sandwich as a result.
- Watch what happens as you add multiple paper clips. They will organize themselves into an even spacing provided you add them carefully.
- Move the wooden stick or straw around inside the sandwich of shielding to see what occurs. The paper clips should be unaffected.
- Now run a steel butter knife’s side to side into the sandwich of shielding to see what occurs. Do the paper clips fall off? Try exploring with other objects, like various metal coins. Keep a checklist of the substances you test, and record any outcomes.
What is Happening?
- The cardboard, the air, as well as other objects like the craft stick and straw are all penetrated by the magnet’s magnetic field lines. Non Permeable materials do not produce magnetic fields but rather permit the passage of magnetic lines of force through them.
- The force lines emanating from the magnet’s pole do not pass through the metal knife, however, because it serves as a magnetic shield. Instead, they are collected, sent along the metal strap, and then brought back into the magnet at the opposite pole. Because they enable the development of magnetic fields within them, materials that collect magnetic lines of force are known as permeable materials. Only magnetic materials may pass through them.
- Use no more than either one or two magnets. It becomes more difficult to avoid the paper clips from dropping as the magnetic field’s strength decreases. How could the sandwich be changed to improve the performance of a weaker magnet?
- Close a pair of metal scissors as though slicing the field lines by sliding them open between the cardboard pieces. When the field lines come into contact with the closed scissors, the paper clips will fall off.
- Scientists analyze magnetic forces employing field lines. You can use a compass to draw field lines since it aligns up along them.
- Along field lines, iron filings also queue up. You can observe the field lines by scattering iron filings on a sheet of paper positioned on top of a magnet .
- A magnet’s north pole generates field lines that travel to the south pole and back. Magnets or iron are subject to a force from the magnetic field lines. Magnetic shielding happens when there aren’t any field lines because without them, there would be no force.
By purposefully rerouting a magnetic field’s field lines, a magnetic field can be kept out of a specific area through the technique of magnetic shielding. Permanent magnets are typically induced for this purpose. A sufficiently wide space may also be enough in some circumstances to produce a shielding effect. If you wish to experiment with the magnetic shielding process but do not know where to begin, then this article will help you out.