Transcript Metric System - Mrs. Daniel's Science Class

Understanding and Using the
METRIC SYSTEM
[SI, Standard International]
Système international
d’Unités
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“I CAN” statements
‗ name the 7 base units
This means that I can identify the correct physical
quantity being represented solely by its unit and/or its
corresponding symbol.
‗ name the most commonly used prefixes
This means that I can list - in the correct order of
magnitude - at least 6, preferably 10, words that precede
any of the base units.
‗ perform metric conversions
This means that I can express a given measurement into
any of the metric prefixes.
Ppt 2010_ES02 Metric System
7 base units
Physical Quantity
Name of Unit
Symbol
Length
meter
m
Mass
gram
g
Time
second
s
Temperature
kelvin
K
Electric current
Ampere
D
Amount of substance
mole
mol
Luminous intensity
candela
cd
Volume liquid is not a fundamental unit, but it is a direct measurement
Volume and Length are linked: 1 Liter (L) occupies 1,000 cm3
Main GOALS and ADVANTAGES are:
i.
A single base unit for any physical quantity
ii. No need for conversion factors
iii. All multiples and subdivisions are
decimal factors or of powers of ten
[prefixes]
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PREFIXES
A WORD that precedes the base unit to identify the
magnitude / the size of the measurement.
i.e. its function is to multiply or divide
the measure by a factor of ten, one hundred, or a positive
integer power of one thousand
Those prefixes are common to all types of measurements.
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PREFIXES [to know]
King
Henri
k
i
l
o
h
e
c
t
o
k
h
DrAnk
d
a
Bad Disgusting Chocolate
b
a
s
e
d
e
c
i
ABBREVIATION
da -- d
Milk
c
e
n
t
i
m
i
l
l
i
c
m
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PREFIXES [to know]
King Henri DAnced Bad Disco Country Music
k
i
l
o
h
e
c
t
o
k
h
c
e
n
t
i
m
i
l
l
i
ABBREVIATION
da -- d c
m
d
a
b
a
s
e
d
e
c
i
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PREFIXES [to know]
King Henri DrAnk Bad D
k
i
l
o
h
e
c
t
o
k
h
d
a
b
a
s
e
isgusting
Chocolate Milk
d
e
c
i
ABBREVIATION
da -- d
c
e
n
t
i
m
i
l
l
i
c
m
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Prefix
Symbol
Magnitude
Meaning
(multiply by)
Tera-
T
1012
1 000 000 000 000
Giga-
G
109
1 000 000 000
Mega-
M
106
1 000 000
kilohectodeca-
k
h
da
103
102
10
1000
100
10
BASE UNIT
-
-
-
decicentimillimicro-
d
c
m
u (mu)
10-1
10-2
10-3
10-6
0.1
0.01
0.001
0.000 001
nano-
n
10-9
0.000 000 001
pico-
p
10-12
0.000 000 000 001
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Prefix
Symbol
Magnitude
Yotta-
Y
1024
Zetta-
Z
1021
ExaPetafemtoatto-
E
P
f
a
1018
1015
10-15
10-18
zepto-
z
10-21
yocto-
y
10-24
Meaning
(multiply by):
1 000 000 000 000 000 000
000 000
1 000 000 000 000 000 000
000
1 000 000 000 000 000 000
1 000 000 000 000 000
0.000 000 000 000 001
0.000 000 000 000 000 001
0.000 000 000 000 000 000
001
0.000 000 000 000 000 000
000 001
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The simplicity of the system is
derived from using the arithmetic
base 10.
One simply needs to shift the
decimal point or change an
exponent to express results with a
different prefix.
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SAMPLE PROBLEM:
AN ANSWER TO A CALCULATION GAVE
A VALUE OF “54,500 meters”
ALTHOUGH ‘CORRECT’, THE VALUE IS
LARGE AND CUMBERSOME; IT CAN BE
SHORTENED AND REDUCED TO A
SMALLER EXPRESSION BY A SIMPLE
CONVERSION…
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kilometer
meter
REMEMBER…
To change to a
larger prefix,
move the decimal to the LEFT
54,500
meters
= 54.5 kilometers
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kilometer
kilo
meter
hecto
deca
BASE
deci
centi
milli
54,000 meters = 54 km
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SAMPLE PROBLEM:
A student has this value for the mass of a
certain object:
1.43 gram
However, the formula in which she has to use the
value calls for the mass in milligrams…
A quick conversion by
moving the decimal point
is easy:
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1.43
gram
gram
REMEMBER…
To change to a
smaller prefix,
move the decimal
to the RIGHT
[fill in zero’s]
milligram
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14.3 decigram
gram
REMEMBER…
To change to a
smaller prefix,
move the decimal
to the RIGHT
[fill in zero’s]
milligram
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143. centigram
gram
= 1,430 REMEMBER…
milligrams
To change to a
smaller prefix,
move the decimal
to the RIGHT
[fill in zero’s]
milligram
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gram
kilo
hecto
deca
BASE
milligram
deci
centi
milli
1.43 gram = 1,430 mg
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To change to a
smaller prefix,
move the decimal to the
RIGHT
[fill in the zero’s, if
necessary]
To change to a
larger prefix,
move the decimal to the LEFT
[fill in the zero’s, if necessary]
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Convert the following
measurement as indicated:
95 cm to meters
A. 0.95 hm
B. 9.5 m
C. 950 m
D. 0.95 m
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Convert the following
measurement as indicated:
1.1 L to milliliters
A. 0.11 mL
B. 11 mL
C. 110 mL
D. 1,100 mL
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Convert the following
measurement as indicated:
17,000 m to kilometers
A. 1,700 km
B. 17 km
C. 170 km
D. 170,000 km
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Convert the following
measurement as indicated:
500 kg to grams
A. 5 g
B. 50 g
C. 500,000 g
D. 0.5 g
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Which SI prefix means one
one-hundredth (1/100)?
A. NanoB. MicroC. MilliD. Centi-
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1) 170.4 m =______________ cm
2)
564 dag =______________ g
3)
58 dg =______________ mg
4)
600 L =______________ kL
5)
0.0923 km =______________ mm
6)
49 hg =______________ g
7)
210 cL =______________ dL
8) 45700 cg =______________ kg
9) 82.4 nm =______________ m
10) 4.51 x 103 L =______________ mL
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ANSWERS
1. 17040cm
2. 5640 g
3. 5800 mg
4. 0.600 kL
5. 92300 mm
6. 4900 g
7. 21.0 dL
8. 0.457 kg
9. 0.0824 m
10.4.51 mL; write out 4.51 x 103 L = 4510 L, the decimal is understood to be
after the zero. Now count UP from the  prefix to the m (milli) prefix. You
counted three places, so move the decimal to the LEFT three places = 4.51 mL
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1. 40 ml = _______ L
2. 5000 L = _______ kl
3. 8 g = _______ kg
4. 12000 L = _______ kl
5. 50 mg = _______ g
6. 6000 m = _______ km
7. 200 kg = _______ g
8. 10000 g = _______ kg
9. 500 ml = _______ L
10. 1 L = _______ ml
11. 4000 L = _______ kl
12. 400 cm = _______ m
13. 20 ml = _______ kl
14. 7000 ml = _______ L
15. 7 cm = _______ mm
16. 9000 L = _______ ml
17. 6 m = _______ mm
18. 1000 cm = _______ m
19. 11 km = _______ m
20. 80 mg = _______ kg
21. 3 m = _______ mm
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Directions: Find the greatest metric measurement in each problem.
1. 500 cm; 5000 mm; 4 m
2. 0.2 L; 240 mL; 50 cL
3. 3000 mg; 250 cg; 3 kg
4. 4 L; 5000 mL; 23,000 cL
5. 17 m; 17,040,000 cm; 17, 400,000,005 mm
6. 2000 cg; 25,300 mg; 2.5 Kg
7. 3400 cg; 4.5 kg; 7,000,843 mg
8. 23 L; 4.3 kL; 6,000,320 mL
9. 820,000 cg; 38 kg; 600,002,394 mg
10. 34,948,304 mL; 32,394 cL; 55 kL
11. 2 km; 5550 m; 64,430 cm
12. 435,678 g; 4.32 kg; 321,900,484 mg
13. 74,000 cm; 824,000 mm; 2 km
14. 84,000 mL; 3.4 kL; 750 L
15. 23,436 g; 268,980 mg; 2.3 kg
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MORE PROBLEMS
http://virtual.yosemite.cc.ca.us/smurov/ex1-1.htm
http://www.fordhamprep.org/gcurran/sho/sho/index.htm
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