Two large glass plates are placed vertically and parallel to one another inside a tank of water, with a separation of 1 mm between the plates. Determine the rise of water in the space between the plates. The surface tension of water is 0.075 N/m .

Step-by-step solution

Let the length of the plates be L and the separation between them be d . The upward force due to surface tension acts along the length of the two plates. Assuming the angle of contact for water and glass to be = 0^ , the upward force is given by: F = 2TL = 2TL The weight of the water column raised to a height h is: W = volume g = (Ldh) g At equilibrium, the upward force balances the weight of the water column: 2TL = Ldh g h = 2T g d Given T = 0.075 N/m , d = 1 mm = 10⁻³ m , = 1000 kg/m ^3 , and taking g = 10 m/s ^2