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How can a button sense your finger without moving?

A touch button can respond without a mechanical switch beneath it. In a capacitive design, a nearby finger changes an electrical property that the circuit can compare with its baseline.

4–5 min

Questions you could explore

  • How does a change in capacitance become a touch decision?
  • How can a touch sensor distinguish a finger from a change in its surroundings?

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Engineering and inventions

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5–7 min

How GPS finds you, and fixes its clock

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Engineering and inventions

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8–10 min

Across an ocean inside a fiber-optic cable

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Engineering and inventions

Bicycle gears and the distance of one pedal turn

Pedaling a bicycle once around in a low gear moves you a short distance with an easy push; pedaling once in a high gear sends you much farther down the road. The ratio of teeth on the front chainring to the rear sprocket explains how a simple chain drive trades pedaling force against distance traveled.

3–5 min

Bicycle gears and the distance of one pedal turn

Engineering and inventions3–5 minPedaling a bicycle once around in a low gear moves you a short distance with an easy push; pedaling once in a high gear sends you much farther down the road. The ratio of teeth on the front chainring to the rear sprocket explains how a simple chain drive trades pedaling force against distance traveled.

How can a button sense your finger without moving? | Speech Topic | speaking.app