Why does a candle make more smoke just after it has been put out?
A candle doesn鈥檛 actually produce smoke after being extinguished, say our readers, and offer some try-at-home experiments to prove this 聽
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What is this shell-like structure (pictured) found in a disused mine?
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Why can鈥檛 I judge bathwater’s temperature with my left hand? (cont)
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This week鈥檚 new questions
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If energy cannot be created or destroyed, where does it come from?
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In the cold, why does our body require warm covers but not our face?
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What caused this red-only rainbow, when there was no rain? (part 2)
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This week鈥檚 new questions
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Why do only some materials glow under UV light?
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What is the best way to store images for the next 100 years? (Part 2)
I want to preserve scenes from my childhood (currently on DVDs) for at least the next 100 years. With technology progressing so rapidly, what is the best format for this? (continued)
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The universe is expanding, but what is it expanding into? (Part 2)
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This week鈥檚 new questions
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How can our own farts smell tolerable when other people鈥檚 smell awful?
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Why are there no birds that hibernate?
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