Weaning Your Baby Onto Solids. The term 'to wean' comes from an ancient phrase that means 'to accustom to'. So weaning refers to the period during which an infant gradually becomes accustomed to food other than milk (breast or formula). Up until 6 months of age, breast or formula milk alone is nutritionally adequate.
Occasional airplane vibration during flight is not unusual. There are many causes of airplane vibration, including landing gear extension and retraction, extension of speed brakes, free play in movable surfaces, and systems malfunctions.
Thankfully, the physics that keeps an airplane aloft is a bit more down to earth. In simple terms, planes are held aloft by lift, the force generated when air flows over and under an airplane wing simultaneously. Air travels faster over the curved top of the wing than below it.