Why are heating radiators placed near the floor and not on the ceiling? (Hint: think about what happens to air when it is heated and how its density changes).
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In a fire, people are advised to move out while staying low or close to the floor. Why is it safer to go low instead of standing up?
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When we pour a cola with ice into a glass, after a while the outside of the glass becomes wet. Where does this water come from if the glass has no holes? (Hint: look at the temperature of the glass and the water vapour in the air).
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