A1.1.6 - Physical properties of water

What are the four physical properties of water?

• bouyancy

• medium viscosity

• high specific heat capacity

• high thermal conductivity

define buoyancy

the upward force exerted on an object when immersed in a fluid

What is the force of buoyancy equivalent to?

weight of the fluid displaced by the object

What is the relationship between object/ fluid density and buoyancy?

• Obj < fluid (density) → buoyancy > gravity exerted on → obj. floats

• Obj > fluid (density) → buoyancy < gravity exerted on obj. → obj. sinks

density

mass (amount of particles) per unit volume

How are bony fish adapted to water’s buoyancy?

they have inflated air-filled swim bladders that control their overall density and thus buoyancy

How are birds adapted to the buoyancy of air?

they have porous bones that reduce their density

How are cyanobacteria adapted to utilize the buoyancy of water, and what are the wider implications of their such adaptations?

give 3 examples of animal adaptations to buoyancy of water and air