Chapter 1Chapter 1Lesson 3 Lesson 3 (cont.)(cont.)

““How to Use the S.I. System” How to Use the S.I. System”

IntroductionIntroduction

mg

Prefix Unit measured

milli gram

I. LengthI. Length

A. Def – the distance between 2 points

1. base unit = meter

2. Examples

a. meter, millimeter, hectometer

Length ExampleLength Example

Convert:

a. 5.0032 meters cm

= 500.32 cm

b. .0034 km mm

= 3400 mm

c. 4567 dm decameters

= 45.67 decameters

II. Volume II. Volume (derived unit)(derived unit)

A. Def. – the amount of space occupied1. formula: length X width X height2. base unit = liter (liquids); meter (solids)

a. **1 cm3 = 1 ml** 3. solids are always cubed (cm3, m3)4. for liquids, use container

dimensions to calculate volume5. is a derived unit which means it is

obtained by combining SI units

Volume ExampleVolume Example

A liquid is poured into a container. If the dimensions of the container are 45 ml, 54 ml, and 80 ml what is the volume of the liquid in ml3?

194,400 cm3

The sides of a box are 45 cm, 54 cm, and 0.4 dm. What is the volume of the box in cm3?

9,720 cm3

III. MassIII. Mass

A. Def. – the amount of matter in an object

1. base unit = gram

2. kilograms is used frequently

3. ex: golf ball vs. table tennis ball

Mass ExampleMass Example

Convert:

a. 54 g kg

.054 kg

b. 3.002 kg mg

3,002,000 mg

IV. Density IV. Density (derived unit)(derived unit)

A. Def. – Mass per unit of volume

1. formula: density = mass / volume

2. derived unit of mass and volume

Density ExampleDensity Example

What is the density of an unknown metal that has a mass of 178.0 grams and a volume of 20.0 mL?

***Remember D=M/V***

8.9 grams/mL

Will this object float in water??? (1.0 g/ml)

V. Time and TemperatureV. Time and Temperature

A. Def. – Time is the interval between two events.

1. Base unit = second

B. Def. – Temperature is the amount of heat contained in a substance

1. Base unit = Kelvin/Celsius

Temperature ScalesTemperature Scales

a. Celsius Scale – used for most scientific worki. 0 = freezing point of waterii. 100 = boiling point of wateriii. 20 = room temperatureiv. 37 = body temperature

b. Kelvin scalei. 0 on the Kelvin Scale is absolute zero (-273 C.)ii. to convert Celsius to Kelvin add 273 Kiii. to convert Kelvin to Celsius subtract 273 K

Temperature ExampleTemperature Example

The outside temperature is 29 degrees Celsius. What is it in Kelvin?

302 Kelvin

A person has a temperature of 313 Kelvin. Does this person have a fever?

yes; the body temp is 40 deg C.