Tag: surface tension

Questions Related to surface tension

A liquid is contained in a vessel. The liquid-solid adhesive force is very as compared to the liquid. The shape of the liquid surface will be

intermolecular forces: cohesive and adhesive forces surface tension properties of matter physics

  1. Horizontal

  2. Vertical

  3. Concave

  4. Convex

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Correct Option: A
Explanation:

If the liquid solid adhesive force is same as that of liquid then the surface will be horizontal at zero angle of contact.

On a clean glass plate a drop of water spreads to form a thin layer whereas a drop of mercury remains almost spherical because

intermolecular forces: cohesive and adhesive forces surface tension properties of matter physics

  1. mercury is a metal

  2. density of mercury is greater than that of water

  3. cohesion of mercury is greater than its adhesion with glass

  4. cohesion of water is greater than its adhesion with glass

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Correct Option: C
Explanation:

Mercury remains spherical on a glass plate due to greater cohesive force between mercury molecules than adhesive force between mercury and glass plate.

A capillary tube of radius $0.25\ mm$ is submerged vertically in water so that $25\ mm$ of its length outside water. The radius of curvature of the meniscus will be $(T = 7.5\times 10^{-3} N/m)$.

intermolecular forces: cohesive and adhesive forces surface tension properties of matter physics

  1. $0.2\ mm$

  2. $0.4\ mm$

  3. $0.6\ mm$

  4. $0.8\ mm$

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Correct Option: C
Explanation:

$h= \dfrac{2T}{dgx}$

$h= \dfrac{2\times 7.5 \times {10}^-3} {1000 \times 10 \times d}$
$h=25mm$
$d= 0.6 mm$