Surface tension is the special property of a liquid due to which the liquid tends to minimize its surface area. This property is due to a net inward imbalanced force due to the fact that no liquid molecules are above the liquid surface molecules. Also due to this the liquid behaves as it is a stretched membrane and there are many practical evidences that prove it is stretched membrane. My question is why does it behave as a stretched membrane that is like ground basically shouldn't it be actually other way round because there is an inward force on surface molecules not outward which are pushing it inward and it is a layer which is actually being pulled inward due to force by other molecules so why does it show a property of stretched membrane as if it were experiencing a force outward or some repulsion and hence support a object on it or behave as a stretched membrane. Please explain in detail theoretically. Also I know there are similar questions regarding this. I have read them and none of them answer what I want. May someone help?

  • $\begingroup$ There is an unbalance between the cohesive and adhesive forces which causes surface tension to occur. $\endgroup$ – UKH Nov 28 '16 at 13:05

The air pressure inside the soap bubble is greater than the air pressure outside the bubble.
On the surface of the soap bubble the forces between the molecules (surface tension) have an inward component which must be balanced by an outward force due to the air molecules inside the bubble the surface being at a higher pressure than the air molecules outside the soap bubble.

  • $\begingroup$ I did not ask anything about a soap bubble or anything related to it. If you are trting to explain my answer using this than can you please elaborate ? $\endgroup$ – Matt Nov 28 '16 at 10:06
  • $\begingroup$ I could have chosen a water droplet where again due the forces on the molecules on the surface there are inward forces acting which is equivalent to pulling the surface of the liquid inwards just like a stretched membrane. $\endgroup$ – Farcher Nov 28 '16 at 10:10

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