RELATIONSHIP BETWEEN BUOYANCY

AND DENSITY

Why do some object float and some sink?

what is bouyancy?

Buoyancy of object is the ability of object to float when we put the object into a liquid

Buoyancy of liquid is the ability of liquid to float when we put it into a different type of liquid

buoyancy

Density of water = 1.0g/cm3

A substance that has a density lower than 1.0g/cm3 will float in water

A substance that has a density higher than 1.0g/cm3 will sink in water

Density of cork is 0.25g/cm3

Density of water is 1.0g/cm3

The density of cork is less than the density of water.

Therefore, cork floats in water

Example 1

Density of glass is 2.6g/cm3

Density of water is 1.0g/cm3

The density of glass is than the density of water.

Therefore, glass in water

Example 2

Density of kerosene is 0.7g/cm3

Density of water is 1.0g/cm3

The density of kerosene is than the density of water.

Therefore, kerosene in water

Example 3

Ice float in water. What can you say about the density of ice compared to the density of water?

We can infer the density of ice is less than the density of water

Example 4

density of water is 1.0g/cm3

Density of cork is 0.25g/cm3

Density of wax is 0.95g/cm3

Density of kerosene is 0.7g/cm3

Density of glass is 2.6g/cm3

These substances were mixed. Arrange them according to their densities.

Example 5

Density of object can be changed by changing its volume

Density of object decreased when volume increased (mass not changed)

Solving simple problems related to density

1) cooking gas cylinder and aerosol cans contain liquefied gas. Gas turns into liquid when it is kept under high pressure

Use of properties of matter in everyday life