Metric System - Lompoc Unified School District / Home
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Metric System
Scientific Notation
In science, we deal with some very
LARGE numbers:
1 mole = 602000000000000000000000
In science, we deal with some very
SMALL numbers:
Mass of an electron =
0.000000000000000000000000000000091 kg
Scientific Notation:
A method of representing very large or
very small numbers in the form:
M x 10n
M is a number between 1 and 10
n is an integer
.
2 500 000 000
9 8 7 6 5 4 3 2 1
Step #1: Insert an understood decimal point
Step #2: Decide where the decimal must end
up so that one number is to its left
Step #3: Count how many places you bounce
the decimal point
Step #4: Re-write in the form M x 10n
2.5 x
9
10
The exponent is the
number of places we
moved the decimal.
0.0000579
1 2 3 4 5
Step #2: Decide where the decimal must end
up so that one number is to its left
Step #3: Count how many places you bounce
the decimal point
Step #4: Re-write in the form M x 10n
5.79 x
-5
10
The exponent is negative
because the number we
started with was less
than 1.
6
10
4 x
Multiply the front
6
x 3 x 10
numbers then add
12 x 1012 the exponents
1.2 x 1013
Move the decimal
behind the first
number
109
1.2 x
3 x 104
0.4 x 105
4 x 104
Divide the front
numbers then
subtract the
exponents
Move the decimal
behind the first
number
SI System
Standard International System of measurement – metrics
Has seven base units and many other units derived from
these seven
Seven Base Units
Mass vs Weight
Mass is not the same as weight
Mass is the amount of matter in a substance
Weight is a measure of the pull of gravity on the substance
Can you be weightless? Can you be massless?
Derived Units
Many other units are used in the metric system, but they are
combinations of the base units
Speed - meter per sec (m/sec)
Volume
volume = length x width x height
(m) x (m) x (m) = m3
.001 m3 = 1 liter (L)
1 cm3 = 1ml
Prefixes
Metric system utilizes prefixes which indicate multiples of 10 of
the unit
kilohectodekadecicentimilli-
k
h
da
d
c
m
1000
100
10
.1
.01
.001
Converting Between Metric Units
3.65 dam = __________cm
2587 mm = __________hm
.0087 hl = __________cl
More Prefixes
Use the appropriate prefixes
3 x 106 L
15 x 10-9 g
8 x 108 m
3.5 x 10-6 A
1.46 x 1010 J
Temperature
Metric unit – Kelvin – not used for measurement
Measured in C (celsius)
K = C + 273.15
Old system is F (farenheit)
C = 5/9 (F -32)
What is 69 F in C and K?