{"id":68612,"date":"2026-10-19T04:30:49","date_gmt":"2026-10-18T19:30:49","guid":{"rendered":"https:\/\/phys-edu.net\/wp\/?p=68612"},"modified":"2026-10-19T04:30:49","modified_gmt":"2026-10-18T19:30:49","slug":"needle-moving-without-a-battery-a-magical-coil-and-magnet-experiment-electromagnetic-induction","status":"publish","type":"post","link":"https:\/\/phys-edu.net\/wp\/?p=68612&lang=en","title":{"rendered":"Needle Moving Without a Battery? A Magical Coil-and-Magnet Experiment (Electromagnetic Induction)"},"content":{"rendered":"

Ken Kuwako, Science Trainer here. Every day is an experiment.<\/strong><\/span><\/p>\n

No batteries. No outlet. Just a magnet moving near a coil, and suddenly electricity flows. No matter how many times I see it, it still makes me say, “Wait, what?!” This is electromagnetic induction. Move a magnet toward a coil and current flows. Hold it still and the current stops. Pull it away and the current flows again. The energy from your moving hand (kinetic energy) turns into electrical energy, which is pretty amazing when you think about it. In this article, I’ll show you how to experience electromagnetic induction for yourself.<\/span><\/p>\n

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First, a Teacher Demonstration<\/h3>\n

We started with a demonstration by the teacher, using Pascal wire. The wire was connected to a galvanometer (a device that detects very small electric currents), and then a magnet was moved toward and away from the wire.<\/p>\n

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Next, the Pascal wire was wound into a coil, and the same experiment was repeated. Keep an eye on the galvanometer needle. How does its movement differ between a single straight wire and a coil?<\/p>\n

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Now It’s the Students’ Turn!<\/h3>\n

Next, the students got to try the experiment with their own hands.<\/p>\n

What You’ll Need<\/p>\n

\u30fbPascal wire
\n\u30fbA coil
\n\u30fbA bar magnet
\n\u30fbA galvanometer<\/p>\n

Steps<\/p>\n

1\u3000Move the magnet toward and away from the coil, and watch how the galvanometer needle moves.<\/p>\n

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2\u3000Change how you move the magnet (try moving it quickly, then slowly).<\/p>\n

3\u3000Swap in a coil with a different number of turns and repeat the experiment.<\/p>\n

4\u3000Stack two magnets together and try it again.<\/p>\n

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