Mon Prof Augmenté
Compact Shape Holds Heat
For the same mass, a smooth, round body has less skin on the outside than a body stretched into a long neck, tail, and limbs. That smaller skin area lets heat escape more slowly in the cold.
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Age 12: open this week
Browse Age 12
In the picture
- Smooth rounded flank
- Small side flipper
- Long neck
- Long tail
- Slim front leg
Examples
- A round potato cools more slowly than the same potato cut into thin strips.
- A penguin keeps warm better than a long-legged bird of the same weight.
Key takeaways
- A compact shape has less skin surface for the same mass.
- Less exposed skin means slower heat loss in cold air or water.
Carry on in the app
Three questions on this lesson. It has left the free week, so its quiz is for subscribers.
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