NEET-XII-Physics

14: Some Mechanical Properties of Matter

with Solutions - page 4
Qstn# iii-6 Prvs-QstnNext-Qstn
  • #6
    When a capillary tube is dipped into a liquid, the liquid neither rises nor falls in the capillary.
    (a) The surface tension of the liquid must be zero.
    (b) The contact angle must be 90°.
    (c) The surface tension may be zero.
    (d) The contact angle may be 90°.
    digAnsr:   c,d
    Ans : (c),
    (d)
    If the liquid level does not rise, it may be assumed that the surface tension is zero or the contact angle is 90°, or both. However, we cannot tell for sure whether the surface tension of the liquid is zero or the contact angle is 0°.
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