Same chapter3 marksDifficulty: Medium
What is thermal expansion? Give one everyday example of it being allowed for.
Heat and Energy
3 marksDifficulty: Medium
What is the anomalous expansion of water and state one of its consequences.
Original Khojo Papers practice question — not from a past board paper.
Answer
Water contracts instead of expanding when it is heated from 0 °C to 4 °C, and expands only above 4 °C, so it is densest at 4 °C. In a pond in winter the water at 4 °C sinks to the bottom while the colder water stays on top and freezes there, so fish survive under the ice.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
The same behaviour is why water pipes burst when the water in them freezes.
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