Mon Prof Augmenté
Dark Needle Mound in the Sun
Sunlight falls on the dark needle mound and warms the needles packed inside. Opening and closing the round doorways lets warm air move, so the mound holds a steady temperature.
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In the picture
- Dark needle surface on the sunny side, where the light lands.
- Round doorway on the sunny slope, standing open, with warm air curling out.
- Round doorway on the shaded slope, filled with a plug of packed needles.
- Air gap between needles inside the mound.
Examples
- A compost heap stays warm inside even on a cold morning.
- A dark stone bench feels hot after the sun has been on it.
Key takeaways
- Dark surfaces soak up sunlight and turn it into heat.
- Opening or closing doorways moves warm air and keeps the temperature steady.
Carry on in the app
Three questions on this lesson. It has left the free week, so its quiz is for subscribers.
At least one new illustrated lesson every weekday for your child’s year, with its quiz and a reminder at 6:15 pm.
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