Week 3: Magnets!

What are some “real life” applications of magnetism?

Magnets are EVERYWHERE! Even the ability to unlock your car door requires magnets (electromagnets, but magnets nonetheless)! Magnets are used to hold stuff up on the fridge, in a compass to navigate, medical equipment (MRIs), you name it! 

What experience have you had with magnets in your life?

Beyond the every day uses of magnets, I also have studied electromagnetism. I have a fairly firm understanding of the basic properties of magnets. Most of my understanding of magnetic interactions stems from my knowledge of electricity and how charged objects interact though. 

What ideas do you have about the science of magnets?

That magnets have two poles (a North end and a South end), there are different kinds of magnets, like permanent magnets and electromagnets, the fundamentals of magnetic fields, and that Earth acts just like a giant bar magnet (with the South end located in the Arctic).

Carry out the investigation: What did you find?

I mostly discovered that my understanding of magnets was flawed. I have a much deeper understanding of electricity and the ability to induce an electric charge on neutral objects that was entirely useless in this investigation. The ability to shield a paperclip from the rare-earth magnet was a property of the shielding material, which is what I predicted. My original thought was that the materials that can easily transfer charge would (possibly) be able to shield the paperclip because magnetism and electricity are so closely connected. Turns out, inducing magnetization is due to how easily the outermost electrons of a material can have it's outer electrons align their spin the match the magnetic field. Iron can do this really well, which is why it was the only material that could make the paperclip drop.   

 

What did you explore and what did you learn?

We mostly explored the idea of the north and south poles, and what effect that had on the system. We also explored the idea of shielding the paperclip with a permanent magnet instead of a neutral material. We found that if we faced the same pole of the magnets towards each other, the paperclip would drop. We were also curious about magnitude of the induced magnetic field and how we could quantify that. We found that if we made a chain of 3 paperclips, removed the magnet then removed the last paperclip, we could pick up the 3rd paperclip with just the chain. If we started with only 2, we couldn't pick up a third.