{"id":69005,"date":"2026-10-29T04:21:32","date_gmt":"2026-10-28T19:21:32","guid":{"rendered":"https:\/\/phys-edu.net\/wp\/?p=69005"},"modified":"2026-10-29T04:21:32","modified_gmt":"2026-10-28T19:21:32","slug":"how-does-wireless-charging-work-the-secret-behind-coils-and-magnetic-fields","status":"publish","type":"post","link":"https:\/\/phys-edu.net\/wp\/?p=69005&lang=en","title":{"rendered":"How Does Wireless Charging Work? The Secret Behind Coils and Magnetic Fields"},"content":{"rendered":"

Hi, I’m Ken Kuwako, your friendly science trainer. Every day is an experiment!<\/strong><\/span><\/p>\n

Your phone is about to die, and you can’t find your Lightning cable anywhere… Then you spot a wireless charger sitting right there, and you could almost shout, “Saved!”<\/p>\n

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But when you stop to think about it, it’s kind of strange. There’s no cable connecting anything, so how does electricity get to your phone just by resting it on a pad?<\/p>\n

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It feels like magic, but it’s actually explained by a law of physics discovered about 200 years ago.<\/p>\n

Let’s Peek Inside a Wireless Charger<\/h3>\n

If you take a wireless charger apart, you’ll find a coil inside.<\/p>\n

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Your smartphone has a coil inside too. Here’s what it looks like when it’s taken apart.<\/p>\n

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One coil sends power and the other receives it. Wireless charging works because these two coils face each other. Together with my student teacher, Mr. I, I designed a lesson to uncover the secret behind wireless charging. There were lots of moments where students had to think for themselves, and I think it turned out to be a really fun class.<\/p>\n

The Equipment We Used<\/h3>\n

Here’s what you’ll need.<\/p>\n

A tester (multimeter), Pascal wire (we’ll call this the “thick coil”), a bundle of enameled wire (we’ll call this the “thin coil”), and a power supply.<\/p>\n

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I bought the Pascal wire here:<\/p>\n

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Fuji Electric Wire Industry VCTF 0.3sq \u00d7 6-core cable<\/a><\/p>\n

This time I used the 6-core version. Cut it into 1 m lengths, then connect the wires at both ends, shifting each connection over by one. You end up with a coil that loops around 6 times, which means you’ve turned 6 m of wire into a single coil.<\/p>\n

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Even with up to 3 A running through it, it stays cool and safe.<\/p>\n

You can learn more about Pascal wire here.<\/p>\n

1\u672c\u306710\u672c\u5206!?\u300c30\u30a2\u30f3\u30da\u30a2\u7d1a\u300d\u306e\u78c1\u5834\u3092\u4f53\u9a13\u3067\u304d\u308b\u30d1\u30b9\u30ab\u30eb\u96fb\u7dda\uff08S-cable\uff09<\/a><\/p><\/blockquote>\n