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Why does an object feel lighter in water than in air?


In air, there is a bouyant force equal to the mass of air being displaced by the object, and if the object is on a horizontal surface, an equal and opposite force of the weight of the object (normal force). According to Archimede's principle, in water there is also a bouyant force, equal to the mass of the water displaced by the object, pushing up on the object, and also a normal force if the object is resting on a horizontal surface. However, since air is less dense than water, the bouyant force of air is less than that of water, so the object in air seems heavier.