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प्रश्न
Why does the bottom of a lake not freeze in severe winter though the surface is all frozen?
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उत्तर
Lakes don’t completely freeze because the ice (and eventually snow) on the surface acts to insulate die water below. To freeze water into ice, a large quantity of heat is to be withdrawn. This heat cannot be
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संबंधित प्रश्न
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(a) solid,
(b) liquid,
(c) gas
(d) vacuum
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Wooden board
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| 2. | Temperature | b. | Form of energy |
| 3. | Black surface | c. | Insulators |
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