🧪 Water Surface Tension Lab

Explore water's extraordinary cohesive hydrogen-bond surface tension ($\sigma = 72.86\text{ mN/m}$). Calculate Jurin's Law capillary rise ($h = \frac{2\sigma\cos\theta}{\rho g r}$) and Young-Laplace droplet excess pressure ($\Delta P = \frac{2\sigma}{R}$).

Water Temp ($T$) °C

Capillary Tube Radius ($r$) mm (inner radius)

Contact Angle ($\theta$) Degrees (0° = Clean glass)

Surfactant / Additive

Capillary Action: Smaller tube radius produces higher liquid elevation ($h \propto 1/r$)

Surface Tension ($\sigma$)

72.75 mN/m

72.75 dyn/cm

Capillary Rise Height ($h$)

29.7 mm

Capillary Elevation

Young-Laplace ($\Delta P$)

291 Pa

Meniscus pressure jump

Capillary Length ($l_c$)

2.72 mm

$\sqrt{\sigma / (\rho g)}$