The upward force that allows a body in a fluid to rise or float is called what?

The upward force that allows a body in a fluid to rise or float is called what?

• A. Altimeter
• B. Tow plane
• C. Buoyancy
• D. Wave

Answer: (C)

The upward force that allows a body in a fluid to rise or float is buoyancy. This force arises because pressure in a fluid increases with depth, creating a net upward push on the submerged object. By Archimedes’ principle, the buoyant force equals the weight of the fluid displaced by the object, which can be expressed as ρ_fluid × V_submerged × g. If the object’s weight is less than this buoyant force, it rises; if it’s greater, it sinks; if they are equal, the object is neutrally buoyant and stays suspended. In air, buoyancy exists but is usually small; in water it’s much more noticeable. The other terms listed—altimeter, tow plane, and wave—do not describe the lifting force on a body in a fluid.

The upward force that allows a body in a fluid to rise or float is buoyancy. This force arises because pressure in a fluid increases with depth, creating a net upward push on the submerged object. By Archimedes’ principle, the buoyant force equals the weight of the fluid displaced by the object, which can be expressed as ρ_fluid × V_submerged × g. If the object’s weight is less than this buoyant force, it rises; if it’s greater, it sinks; if they are equal, the object is neutrally buoyant and stays suspended. In air, buoyancy exists but is usually small; in water it’s much more noticeable. The other terms listed—altimeter, tow plane, and wave—do not describe the lifting force on a body in a fluid.