What are the principles on which the operation of the hygrometer and psychrometer is based.

Psychrometer and hygrometer are devices that measure air temperature and humidity.

1) The principle of operation of the psychrometer is based on the evaporation of liquid, and the temperature difference is indicated by a wet and dry thermometer. Based on the difference in temperatures between a humid object and the environment, information about the relative humidity of the air is revealed.

2) The principle of operation of a hygrometer is based on a change in the physical properties of substances in connection with a change in the humidity of the environment.