2 2 units of measurement n.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
2-2: Units of Measurement PowerPoint Presentation
Download Presentation
2-2: Units of Measurement

Loading in 2 Seconds...

play fullscreen
1 / 18

2-2: Units of Measurement - PowerPoint PPT Presentation


  • 233 Views
  • Uploaded on

2-2: Units of Measurement. Objectives: Name SI units for length, mass, time, volume, and density Distinguish between mass and weight Perform density calculations Transform a statement of equality to a conversion factor. SI Measurement. Le Systeme International d’Unites Abbreviated SI

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about '2-2: Units of Measurement' - maxime


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
2 2 units of measurement

2-2: Units of Measurement

Objectives:

Name SI units for length, mass, time, volume, and density

Distinguish between mass and weight

Perform density calculations

Transform a statement of equality to a conversion factor

si measurement
SI Measurement
  • Le Systeme International d’Unites
    • Abbreviated SI
    • Adopted 1960 as world-wide agreed upon standards
    • Defined in terms of standards of measurements
si base units
SI Base Units
  • There are 7 base units in SI
some si base units
Some SI Base Units
  • Mass
    • A measure of the amount of matter in an object
    • SI unit for mass is the kilogram (kg)
    • The gram (g) is more useful for measure masses of small objects
    • The milligram (mg) is used for even smaller objects
  • Length
    • SI standard unit for length is the meter (m)
    • The kilometer (km) is used to express longer distances
    • The centimeter (cm) is used to express shorter distances
metric prefixes
Metric Prefixes
  • Prefixes are added to the names of SI base units to represent quantities that are larger or smaller than the base units
derived si units
Derived SI Units
  • Derived units: combinations of SI base units
    • Produced by multiplying or dividing standard units
    • Examples:
      • Area m2 length x width
      • Volume m3 length x width x width
      • Density
slide7

Volume

    • Volume: the amount of space occupied by an object
    • The derived SI unit is cubic meters (m3)
      • One cubic meter = the volume of a cube whose edges are 1 m long
    • Cubic centimeter (cm3) is usually used because m3 is a very large unit
    • Volumes of liquids and gases are often measured by a non-SI unit called the liter (L)
      • 1 L = 1000 cm3
    • The milliliter (mL) is used for smaller volumes
      • 1000 mL = 1 L
    • 1000 mL = 1 L = 1000 cm3 1 mL = 1 cm3!
slide8

Density

    • Density: the ratio of mass to volume, or mass divided by volume
    • The SI unit for density is
      •  Units are too large!
    • Unit often used is grams or
    • A characteristic physical property of a substance
      • Can be used as one property to help identify a substance
slide9

m

Helpful hint:

D

V

m

m

V

D

V

D

sample problem
Sample Problem
  • A sample of aluminum has a mass of 8.4 g. The volume of the sample is 3.1 cm3. Calculate the density of the aluminum.
    • Given: mass (m) = 8.4 g volume (V) = 3.1 cm3
    • Unknown: density (D)
    • You know that
      • Plug in the values!
you try
You Try!
  • What is the density of a block of marble that occupied 310 cm3 and has a mass of 853 g?
    • 2.75 g/cm3
  • Diamond has a density of 3.26 g/cm3. What is the mass of a diamond that has a volume of 0.350 cm3?
    • 1.14 g
  • What is the volume of a sample of liquid mercury that has a mass of 76.2 g, given that the density of mercury is 13.6 g/mL?
    • 5.60 mL
conversion factors
Conversion Factors
  • Conversion factor: a ratio from the equality between two different units that can be used to convert from one unit to the other
    • Example:
      • 1 dollar = 4 quarters or 4 quarters = 1 dollar
        • or
  • When you want to use a conversion factor to change a unit in a problem, you can set up the problem the following way:
      • Example: How many quarters are in 12 dollars?
slide14

You can convert factors if you know the relationship between the unit you have and the unit you want!

    • Example:
      • deci- means “1/10”
      • 1 meter (m) = 10 decimeters (dm)

AND

      • deci- also means “0.1”
      • 0.1 meter (m) = 1 decimeter (dm)

 You can write the following conversion factors relating meters and decimeters

sample problem1
Sample Problem
  • Express a mass of 5.712 grams in milligrams and in kilograms.
    • Given: 5.712 g
    • Unknown: mass in mg and kg
    • Solution:
      •  mg: The expression that relates grams to milligrams is 1 mg = 0.001 g
        • The possible conversion factors are
      •  kg: To find kilogram is similar 1 kg = 1000 g
        • The possible conversion factors are
you try1
You Try!
  • Express a length of 16.45 m in centimeters and in kilometers.
    • Answers:
    • 1645 cm
    • 0.01645 km
stair step method

1000

Stair Step Method

100

Kilo-

10

Hecto-

Deka-

1

0.1

King

Base

Unit

0.01

Henry

Deci-

0.001

Centi-

Died

By

Milli-

Drinking

Base units:

Mass = Gram (g)

Length = Meter (m)

Volume = Liter (L)

Chocolate

Milk

you try2
You Try!
  • Express a mass of 0.014 mg in grams.
    • Answer: 0.000014 g