It is important that scientists can communicate with each other.
Measurements
Measurement: comparison of some aspect (dimensions,
quantity, capacity) of an objector phenomenon with a
.
 The
makes the measurement
 All measurements need a
and
.
for
comparison.
Use
in measurements:
kilo = 1000
deci = 1/10
hecto = 100
centi = 1/100
deka = 10
milli = 1/1000
Scientists use metric units to measure
, density, and
, volume, mass,
.
It is easier to convert meters to centimeters or millimeters
than to go from yards to feet or inches. All you have to do with
the metric system is move decimal places.
Precision: gives a better representation of the value.
 2.1cm is more precise it is measured to the nearest
tenth of a cm
 2cm is only measured to the nearest cm
Length
Metric standard for length is the
(m)
1 m = 100 cm = 1000 mm
(1) m
(1/100) m (1/1000) m
Whereas:
1000m = 1 km
What if you wanted to measure something the size of an atom?
Angstrom = one ten billionth of a meter
Sometimes we are given a unit that we don’t want; we need to
use a
to get the unit we want.
For example: Given 5m want the measurement in cm
Using conversions
We know that 100cm = 1 m
Therefore we can set up a conversion
2km =
m
5mm =
m
6.3m =
cm