Question: Two large glass plates are placed vertically and parallel to each other inside a tank of water with ...

Question

Two large glass plates are placed vertically and parallel to each other inside a tank of water with separation between the plates equal to 1 mm. Find the rise of water in the space between the plates. Surface tension of water = 0.075 N/m. (Contact angle = 0°).

Answer 1

Solution

The capillary rise between two plates is given by:

h = \frac{2\gamma \cos \theta}{\rho g d}

Given: $\gamma = 0.075 \, \text{N/m}$ , $\theta = 0^\circ$ (so $\cos\theta = 1$ ), $d = 0.001 \, \text{m}$ , $\rho = 1000 \, \text{kg/m}^3$ , and $g = 9.8 \, \text{m/s}^2$ .

Substitute the values:

h = \frac{2 \times 0.075}{1000 \times 9.8 \times 0.001} = \frac{0.15}{9.8} \approx 0.0153 \, \text{m} = 1.53 \, \text{cm}