Cooking in the kitchen in winter, a little more careful friends will find that the outside world is not clear and the inner surface of the window becomes blurred; In fact, this is an attached liquid surface, composed of countless tiny water droplets, which is different from the traditional uniform water surface; Moreover, because the light hits the window and is reflected back and forth by countless small drops of water, the light wave will become bent countless times, resulting in unclear outside.

Most importantly, why is there a dense layer of water droplets attached to the inner surface of the window?

First of all, when cooking in the kitchen, because the food is heated by fire, the water contained in the solid food is evaporated, and the water in the liquid food is relatively more turned into steam, which makes the air humidity in the kitchen room higher and higher. The air outside the window is cold, so there are: kitchen air temperature >; Window glass temperature >; Outside air temperature (obvious temperature difference and thermal difference); When water vapor is cold, it will release heat and liquefy, so a layer of water drops will be formed on the inner surface of the window glass.

In fact, this can be analyzed and explained in depth, so that everyone can better understand this principle and its related principles, similar to the differential method in advanced mathematics: suppose there are countless planes in the kitchen, which are vertical and parallel to the glass surface of the window, and each plane contains a certain amount of water (steam); We know that the shape of fluid (liquid and gas) is relatively unstable, and it always flows and moves in the direction of relatively uniform, stable and balanced concentration; Every time the water vapor on the inner surface of the window liquefies into water, the plane water vapor becomes zero, and every next plane will flow to the plane closer to the inner surface of the window until the concentration of water vapor contained in each plane is equal; Repeatedly take countless small steps until the inner surface of the window contains enough water droplets and other planes contain enough water vapor to reach another relative balance, and the relative motion will stop. Otherwise, there won't be so many water droplets on the inner surface of the window, which makes people see enough.