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प्रश्न
Angle of contact for the pair of pure water with clean glass is _______.
विकल्प
acute
obtuse
90o
0o
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उत्तर
0o
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संबंधित प्रश्न
In which of the following substances, surface tension increases with increase in temperature ?
- Copper
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- Iron
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'n' droplets of equal size of radius r coalesce to form a bigger drop of radius R. The energy liberated is equal to...................
(T =Surface tension of water)
`(a) 4piR^2T[n^(1/3)-1]`
`(b) 4pir^2T[n^(1/3)-1]`
`(c) 4piR^2T[n^(2/3)-1]`
`(d)4 pir^2T[n^(2/3)-1]`
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