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WHYWhy does…? · #14EP.166 · 24 s

Why does…? #14: How does an induction cooktop heat only the pan?

Cover of the lesson: Why does…? #14: How does an induction cooktop heat only the pan?Coming to YouTube soon
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// WHAT YOU WILL LEARN

A coil under the glass makes a fast-flipping magnetic field; it drives eddy currents inside the iron pan, so the pan heats itself while the glass only gets warm from the pan.

// LESSON NOTES

Why does the pan get hot… but the glass doesn't? 🍳🔥

Under the glass of an induction cooktop hides a big flat coil of copper wire 🌀
⚡ Its current swings back and forth about 20,000 times a second — so its magnetic field flips just as fast.
🔁 That flipping field makes swirling currents (eddy currents) inside the iron pan, and the pan heats ITSELF.

🧊 An ice cube on the glass next to it? It barely melts!
The glass only gets warm from the hot pan sitting on it.

💡 Tip: if a magnet sticks to your pan, it works on induction.

Read the voiceover (transcript)
  1. Why does the pan get hot, but not the glass?
  2. Under the glass hides a big coil of copper wire!
  3. Its current swings back and forth twenty thousand times a second!
  4. That magnetic field spins swirling currents inside the iron pan!
  5. Guess: does this ice cube melt?
  6. Barely! The pan heats itself!
  7. The glass only gets warm from the hot pan.
  8. Next: why does your phone charge slower near full? Follow for more!

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