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प्रश्न
An ice cube is suspended in vacuum in a gravity free hall. As the ice melts it
पर्याय
will retain its cubical shape
will change its shape to spherical
will fall down on the floor of the hall
will fly up.
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उत्तर
As the ice cube melts completely, the water thus formed will have minimum surface area due to its surface tension. Any state of matter that has a minimum surface area to its volume takes the shape of a sphere. Therefore, as the ice melts, it will take the shape of a sphere.
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संबंधित प्रश्न
Derive an expression for excess pressure inside a drop of liquid.
In which of the following substances, surface tension increases with increase in temperature ?
- Copper
- Molten copper
- Iron
- Molten iron
'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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State any two characteristics of the angle of contact
Viscosity is a property of
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(a) the material of the solid
(b) the material of the liquid
(c) the shape of the solid
(d) the mass of the solid
A drop of mercury of radius 2 mm is split into 8 identical droplets. Find the increase in surface energy. Surface tension of mercury = 0.465 J m−2.
A capillary tube of radius 1 mm is kept vertical with the lower end in water. (a) Find the height of water raised in the capillary. (b) If the length of the capillary tube is half the answer of part , find the angle θ made by the water surface in the capillary with the wall.
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Insect moves over the surface of water because of ______.
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[T = surface tension of water]
