Correct Answer - Option 1 : 2T/r
Concept:
- Due to surface tension, pressure on the concave side of the liquid is always greater than the pressure on the convex side.
- This is why pressure inside the liquid drop air bubble is greater than the pressure outside.
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Excess pressure inside a liquid drop is given by
\(P= {2T \over r}\)
where T is the surface tension and R is the radius of drop.
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Excess pressure inside an air bubble in the liquid is given by
\(P= {2T \over r}\)
where T is the surface tension and R is the radius of drop.
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Excess pressure inside the soap bubble in the air is given by
\(P= {4T \over r}\)
where T is the surface tension and R is the radius of drop.
Explanation:
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Excess pressure inside a liquid drop is given by
\(P= {2T \over r}\)
where T is the surface tension and R is the radius of drop.
- The reason for this is in a drop there is only one liquid surface that is outside the drop. Inside the drop, there is only liquid.
\(P= 1 \times {2T \over r}={2T \over r}\)
So, Excess pressure inside a liquid drop of surface tension T and radius r is - 2T/r.
