Transcript Standards of Measurement

Standards of
Measurement
Section 1-2
Units and Standards
• Units must be included in order for a
measurement to make sense.


Ball of string just says 150 (no unit) is it
150 feet, inches, meters?
Metric units include meters, centimeters,
kilograms, grams, etc
• Standard is an exact quantity used for
comparison
Example
No meter stick
 Will the desk fit through the door?
 Measure with my hands
 Measure with your hands
 No standard!

International System of Units
Abbreviated SI from the French Le
Systeme Internationale d’Unites
 Improved version of the metric
system
 Each SI measurement has a Base
unit

• Length – meter
• Mass - kilogram
SI Prefixes

Based on Multiples of 10

Milli

Centi

Deci

Meter
Kilo

gram
liter
Converting SI Units
Bridges
 Top of Bridge = Bottom of Bridge
 1 meter = 10 dm
 1 meter = 100 cm
 1 meter = 1000 mm
 1000 meters = 1 km

Convert the following:

1.255 liters to ml

3075 cm to m
More conversions:

11cm
to
mm

675 m

345 mm to
to
km
km
Measuring Distance
Base unit = meter
 Size of the object determines the
unit
 Activity pg.17


13mm is easier to understand than
0.013m
Measuring Volume
Volume = the amount of space an
object occupies.
 Volume = L x W x h (for solids)
 Liquid volumes are measured in liters
and milliliters.
 1 Liter = 1dm3
 1 Liter =1000 ml
 1 cm3 = 1 ml

Conversions

1.5 liters to ml

1.5 liters to cm3
Measuring Matter

Mass = quantity of matter in an
object.
• Ping pong ball and golf ball have the
same volume, but much different
masses

Density = mass per unit volume
• Unit for density could be g/cm3

If an object has a mass of 10g and a
volume of 2 cm3
• Density = 10g/2cm3 or
5g/cm3
Measuring Time and Temp.
Base unit for time is seconds
 Base unit for temp. is Kelvin

• Most scientific work is done using
celsius
• 0 Kelvin is the coldest possible temp.
also know as “absolute zero”
• 0 kelvin= -2730C (273 degrees below
the freezing pt. of water)