1) A rapid change in pressure during takeoff or landing of the aircraft causes discomfort in the middle ear, where the initial pressure on the eardrum lasts longer.
2) Swallowing movements improve air access to the auditory (Eustachian) tube, through which the pressure in the middle ear cavity is equalized with the pressure in the environment.
Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.