Solids

Liquids Gases

Plasmas

Ice Water

Steam

Heat Heat

A solid has definite size and shape.

A liquid has definite size but no definite shape. It takes the shape of its container.

A gas has neither definite size nor definite shape. It takes the size & shape of its container.

States of Matter Solid, Liquid, and Gas

Density

Which weighs more, a kilogram of iron or a kilogram of feathers?

Density = Mass/VolumeWhich is more dense, a kilogram of iron or a kilogram of feathers?

Units of Density: g/cm3, g/mLkg/m3,A rectangular solid has dimensions 8.0 cm long, 5.0 cm wide, and 2.0 cm thick. It has a mass of 1.6 kg. What is its density in g/cm3?

The same!

The iron!

Volume = length x width x thickness

Volume = 8.0 cm x 5.0 cm x 2.0 cm

Volume = 80 cm3

Density = Mass/VolumeDensity = 1600g/80 cm3

Density = 20g/cm3

Mass = 1.6 kg = 1600 g

Density of Water

Water has its maximum density at a temperature of approximately 4o C

Density = Mass/Volume

Density of Water = 1 g/cm3

1 cm3

If the density of an object is less than or equal to 1 g/cm3

1 g of water at a temperature of 4o C has a volume of 1 cm3 (1 mL).

Density of Water = 1 g/mL

, it will float.

If the density of an object is greater than 1 g/cm3 , it will sink.

Measuring Volume

Volume = length x width x thickness

V = L x W x TRectangular Solid

Cylinder

Volume = Cross Sectional Area x LengthV = A x L A = πr2

V = πr2LL

A

Measuring Volume of Irregular Solids

Volume of the irregular solid = Volume of water displaced

V = V2 – V1

Irregular Solid

V1

V2

Using the density of water to measure the volume of a container.

Determine the mass of the empty flask, m1.

Empty Flask

Filled with water

Fill the flask with water.

Determine the mass of the flask & water, m2.

Determine the mass water, m3 , as follows: m3 = m2 – m1

Use the density equation to find the volume. Density = mass /volume

Volume = mass /Density

Volume = m3 /1g/cm3

Volume of the water = Volume of the Flask

SCALING

Scaling

Side = 1 cm

Side = 10 cm

Side = 2 cm

Volume = 8 cm3

Area = 24 cm2

Volume = 1 cm3

Area= 6 cm2

Volume= 1000 cm3

Area = 600 cm2

Area/Volume = 6

Area/Volume = .6

Area/Volume = 3

Scale Factor = 1

Scale Factor = 2

Scale Factor = 10

Area/Volume = 6

Area/Volume = .6

Area/Volume = 3

Scale Factor = 1 Scale Factor = 2

Scale Factor = 10

Heat Loss is proportional to AreaHeat Production is proportional to Volume

Heat Loss/Heat Production = Area/Volume

Heat Loss is 6 times as great as the Heat Production for the small cube.

Heat Loss is .6 times as great as the Heat Production for the cube scaled up by 10.

The small cube losses heat at 10 times the rate as the large cube.

Area/Volume = 6

Area/Volume = .6

Area/Volume = 3

Scale Factor = 1 Scale Factor = 2

Scale Factor = 10

Amount of skin is proportional to AreaWeight is proportional to Volume

Amount of Skin/Weight = Area/Volume

A pound of small potatoes has more skin than a pound of large potatoes.

I you want to make mashed potatoes you get more with large potatoes.

Which is stronger: an elephant or an ant?

“He eats like a horse.”

“She eats like a bird.”

Why does a fly often get water logged and become unable to fly from a body of water?