Explanation

It is also called contact angle. At the junction of solid, liquid and gas phases, the included angle from the solid-liquid interface through the liquid interior to the gas-liquid interface is called the contact angle. Usually represented by 0. Place a drop of liquid on a uniform and smooth solid surface, sometimes with the liquid fully unfolded and covering the solid surface; Sometimes, the droplets stay on the liquid surface and form a certain angle with the same surface, that is, the contact angle.

Classification