Why does an object feel lighter when submerged in water?

An object feels lighter in water because the water exerts an upward buoyant force on it. According to Archimedes' principle, this buoyant force equals the weight of the fluid the object displaces. The buoyant force partially counteracts gravity, so the object's apparent weight is reduced. If the buoyant force equals or exceeds the object's weight, the object floats; if it's less, the object sinks but still feels lighter than in air. Understanding buoyancy — the upward force from a fluid that makes submerged objects feel lighter — is part of the fluids topic.