The upward force of water displaced by the hull is called

• A. TRACTION
• B. LIFT
• C. BUOYANCY
• D. DRAG

Answer: (C)

Buoyancy is the upward force that a fluid exerts on any object immersed in it. For a boat, this force comes from the water displaced by the hull. According to Archimedes’ principle, the buoyant force equals the weight of the water that would be displaced by the submerged part of the hull. This upward push acts vertically and counteracts the boat’s weight, allowing it to float. If the hull displaces more water than the boat weighs, the buoyant force would be greater than the weight and the boat would rise; if it displaces less, the boat would sink.

Traction is the frictional force along a surface and isn’t what supports the boat. Drag is the resistance to motion through water, acting opposite the direction of travel, not upward. Lift is an upward force produced by pressure differences on surfaces (like an airplane wing) and isn’t what keeps a boat afloat; the specific upward support for a boat in water is buoyancy.