Solid and fluid

DBS1012 – ENGINEERING SCIENCE

NUR ELYANI BINTI MUSA

At the end of this chapter, you should be able to ;

Define density of matter and SI Unit

Relative Density of matter and SI Unit

Definition :Matter is anything that has mass and occupies space (volume).

Example of matter : Chair, books, water, wood & others

(rho)

An Object has a mass of 0.75kg and a volume of 5.0 x 10-4m3 .

Solution Given mass : 0.75kg volume = 5.0 x

10-4m3

3

4

/150010575.0

mkg

volumemass

DEFINITION – Ratio of the density of a substance

to the density of water.FORMULA

To compare the densities of two materials, we compare each with the densities of water.

Relative Density didn’t have SI unit.

water

material

sigma

Substances Density(kg/m3) Subtances Densities (kg /m3)

Solids GasesCopper 8890 Air 1.29Iron 7800 Carbon Dioxide 1.96Lead 11300 Carbon

Monoxide1.25

Aluminium 2700 Helium 0.178Ice 917 Hydrogen 0.0899Wood,white pain 420 Oxygen 1.43Concrete 2300 Nitrogen 1.25Cork 240 Ammonium 0.760

Liquids Propane 2.02Water 1000

Table densities for various substances

Seawater 1025Oil 870Mercury 13600Alcohol 790Gasoline 680

water

material

Relative Density

Example 2

Find the relative density if Copper is 8890 kg/m3

and water is 1000 kg/m3 .

)(89.8

/1000/8890

3

3

NoUnit

mkgmkg

QUESTION & ANSWER

SOLIDS LIQUIDS GASES

Concrete Oil -Cork Gasoline -

Copper Mercury -

Lead

•Arrange the matter given according to their density:

Lower

Higher

Float

dense

Calculate the density of the block with mass of 85kg if measurement of block is 0.55 m x 0.44m and find relative density of water. (density of water = 1000 kg/m²)

Definition of Density

SI Unit of density

Definition of Relative density and SI Unit

From the experiment , we know that Anything that floats has a lower density

and anything that sink is more dense.

Thank you