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प्रश्न
In which of the following substances, surface tension increases with increase in temperature ?
- Copper
- Molten copper
- Iron
- Molten iron
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उत्तर
Molten copper
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संबंधित प्रश्न
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`(a) 4piR^2T[n^(1/3)-1]`
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`(c) 4piR^2T[n^(2/3)-1]`
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