# Jurin’s Law | Definition, Formula – Surface Tension

## Jurin’s Law | Definition, Formula – Surface Tension

We are giving a detailed and clear sheet on all Physics Notes that are very useful to understand the Basic Physics Concepts.

Jurin’s Law Definition:
If a capillary tube of insufficient length is placed vertically in a liquid, then liquid never come out from the tube on its own, as

Rh = constant ⇒ R1h1 = R2h2

where,
R = radius of curvature of liquid meniscus and
h = height of liquid column.
When a tube is kept in inclined position in a liquid and the vertical height h remains unchanged, then length of liquid column
Image

cos α = $$\frac{h}{l}$$ or l = $$\frac{h}{cos α}$$

Liquid rises (water in glass capillary) or falls (mercury in glass capillary) due to property of surface tension

Jurin’s Law Formula:

S = $$\frac{R \rho g h}{2 \cos \theta}$$

where,
R = radius of capillary tube,
h = height of liquid,
ρ = density of liquid,
θ = angle of contact,
S = surface tension of liquid and
g = acceleration due to gravity.

Surface Tension:
In Physics, the tension of the surface film of a liquid because of the attraction of the surface particles by the bulk of the liquid, which tries to minimize surface area is called surface tension. When the surface of the liquid is strong enough, then surface tension is applicable. It is strong enough to hold weight.