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What actually makes a popcorn kernel jump?

A popcorn kernel does more than split open: it can launch itself as it expands. A research study examined popping, jumping, and sound as related but distinct events, including the role of expanding starch in the jump. That makes a familiar snack a useful case of separating observations from explanations.

4–6 min

Questions you could explore

  • Why might the pop’s sound and the kernel’s jump need different explanations?
  • How do trapped moisture and the kernel's outer covering contribute to a pop?

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3–5 min

Keeping oil and water together in mayonnaise

Food3–5 minPour oil and water into a jar, shake them hard, and they will quickly separate back into two layers. Yet mayonnaise stays a thick, stable sauce because vigorous whisking breaks the oil into microscopic droplets, while emulsifiers in the egg yolk coat those droplets and stop them from recombining.

What actually makes a popcorn kernel jump? | Speech Topic | speaking.app