Systeme International base units (SI Units)

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Transcript Systeme International base units (SI Units)

Systeme International base units
(SI Units)
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Length
Meter
Mass
gram
Volume
Liter
Time
Second
Temperature Kelvin
Heat
Joule
m
g
L
s
K
J
Written
giga
mega
kilo
Symbol
G
M
k
Exponential
109
106
103
deci
Base unit
d
100
10-1
centi
c
10-2
milli
micro
Nano
m
µ
N
10-3
10-6
10-9
Decimal
1 000 000 000
1 000 000
1 000
1
0.1
0.01
0.001
0.000 001
.000 000 001
• Heat - measure of the quantity
or how much energy
• Temperature - measure of the
intensity or how
energetic each
particle is
Temperature Conversion
K = °C + 273
°C = 5/9 (°F – 32)
°F = 9/5 * °C + 32
Density - The amount of mass
per unit volume
Density = Mass
Volume
D=M
V
Specific Gravity
• Numerically the same as density but has no
units. It is still a mass/volume
• It is a comparision to water as the standard
that has a density of 1.00 g/mL at 20 ºC
• If Lead has a density at 20 ºC of 11.35 g/mL
It is 11.35 times more dense than water
• So the specific gravity for Lead is reported
as 11.35
calorie
The amount of heat needed to
raise the temperature of one
gram of liquid water by 1 ºC
1 kcal = 1000 cal
1cal = 4.184 J
1000 cal = 1 C (food calories)
Specific heat
• The amount of heat
(in calories) necessary to raise
the temperature of 1 g of any
substance by 1 ºC.
Amount of heat = Specific heat x mass x
change in temp
Heat = SH x m x (T2 – T1)