Science Chapter 3:6 Fluid Displacement
Why does a balloon filled with helium rise?
A helium balloon floats in air because it weighs less that the volume of the air it displaces.
How does a submarine change its weight?
Doors are opened that allow water to flood into the ballast tanks (compartments below deck that can be filled with water). By taking on water the submarine become heavier and sinks to displace an equal weight of water.
State Archimedes' principle of buoyancy.
States that buoyant force experienced by an object is exactly equal to the weight of the fluid displaced.
Why are airships limited in the height they can attain?
The atmosphere above the airship is too thin to support it with buoyant force.
Define Buoyancy.
The tendency for a solid object (such as your body) to float when placed in fluid.