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Give reason : Why does a hot substance ...

Give reason :
Why does a hot substance not remain hot after two or three hours in a thermos flask?

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  1. Use your brain power: Why is there a gap at the joints of rails and o...

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  2. Use your brain power: Why is mercury or alcohol used in a thermometer...

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  3. Give reason : Why does a hot substance not remain hot after two or th...

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  4. Rub your palms against each other and put them on your cheeks. What do...

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  5. Apparatus: Bars of stainless steel, aluminium and copper, a candle, a ...

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  6. Apparatus: A beaker, potassium permaganate crystals, a burner, water, ...

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  7. Light a candle and stand it upright. Hold your hands on its two sides ...

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  8. Light a candle and stand it upright. Hold your hands on its two sides ...

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  9. Apparatus: Two aluminium tins of the same size, two small galsses, wat...

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  10. Apparatus: Glass bottle, baloon, hot water, etc. : Procedure: Fix a b...

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  11. Answer the question in short: What is meant by thermoware?

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  12. Oral Work : What is conduction of heat?

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  13. Oral Work : What will happen when only upper part of liquid is heated...

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  14. Oral Work : How does the heat of the sun reach us?

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  15. Oral Work : How can we see objects at night using infrared camera?

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  16. Solve the following crossword puzzle. : Across: Thermos flask was i...

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  17. Project : Make a note of the various example of heat transfer seen in...

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  18. Fill in the blanks. : ……………. (Transfer/Convention) of heat means the ...

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  19. Fill in the blanks. : The ability of a substance to absorb heat radia...

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  20. Answer in one word. : In which of the substances does condition occur...

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