Hunt for the Hidden Magnets in Your Smartphone! The Surprising Truth Revealed by Iron Filings
I’m Ken Kuwako, a science trainer. Every day is an experiment!
The smartphone you hold in your hands every day is hiding several tiny “magnets” inside its slim body. Did you know that? In this experiment, we’ll sprinkle some handy MagChip over a smartphone instead of iron filings and reveal the invisible magnetic fields hiding inside. It’s a simple experiment that makes you feel a little like a science detective!
Sprinkling MagChip over a smartphone
The procedure is incredibly simple. When you sprinkle MagChip over the phone, you’ll notice that it doesn’t spread evenly across the entire surface. Instead, it sticks only to certain spots. Take a look at this video.
In other words, these spots are clues that magnets are hidden inside the phone.
We use our smartphones without giving them a second thought, but once you make their invisible magnetic fields visible, something strange happens: a familiar piece of technology suddenly starts to look like an “unknown device.”
What’s hiding where the MagChip sticks?
So, what exactly is hiding in the places where the MagChip gathers? One possibility is the speaker.
Speakers produce sound by using the forces of attraction and repulsion between a magnet and a coil carrying an electric current. These forces make the diaphragm vibrate, producing sound. In other words, a speaker is a “magnet-based converter” that transforms electrical energy into sound.
Another possibility is the motor used for the phone’s vibration function. When your phone buzzes to let you know about an incoming call or notification, that’s also the result of magnets and coils exerting forces on each other inside the motor.
The area on the right looks suspicious!
A smartphone is actually a “collection of magnets”
This is only a hypothesis, but when you start thinking about it this way, you realize that a tiny smartphone can contain multiple magnets serving very different purposes: producing sound, creating vibrations, and even helping to stabilize the camera and reduce hand shake. We may not notice them because we can’t see them, but it wouldn’t be an exaggeration to say that our everyday lives are supported by the power of magnets.
Experiments that use iron filings or MagChip to visualize magnetic fields aren’t limited to bar magnets and U-shaped magnets. You can also use the same idea to investigate everyday electronic devices like smartphones. I think this is a fascinating experiment because it allows students to realize that the “magnets” and “magnetic fields” they’ve only encountered in textbooks are actually real phenomena hiding inside something they carry in their own pockets.
Why not give it a try with your own smartphone? Keep in mind that the arrangement of magnets inside can vary depending on the model, so please try this experiment at your own risk.
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