1.
What is measurement?
• The process of comparing the
quantity of an observable relative to
a standard.
Example:
– Measuring the length of pencil using a
ruler
– Determining how heavy you are using a
weighing scale
2.
How should measurements
be reported?
• All measurements must be given
with the correct units.
• All measurements must be given
with the correct number of
significant figures (sf’s).
3.
English System of Measurement
• This system grew out of the creative
ways that people measured for
themselves. Familiar objects and
parts of the body were used as
measuring devices.
4.
English System of Measurement
• This system grew out of the creative
ways that people measured for
themselves. Familiar objects and
parts of the body were used as
measuring devices.
5.
English System of Measurement
• Unfortunately, these creative
measuring devices allowed for
different measurements to be
obtained when different people
measured the same items.
• Eventually, a standard was set so
that all measurements represented
the same amount for everyone.
6.
Conversion within the English System
Length:
12 inches (in) = 1 foot (ft)
3 feet = 1 yard (yd)
5280 feet = 1 mile (mi)
Weight:
16 ounces (oz) = 1 pound (lb)
2000 lb = 1 ton
7.
Conversion within the English System
Capacity:
3 teaspoons (tsp) = 1 tablespoon (tbsp)
16 tbsp = 1 cup (c)
8 ounces (oz) = 1 c
2 c = 1 pint (pt)
2 pt = 1 quart (qt)
4 qt = 1 gallon (gal)
8.
International System of Units
Systeme International des Unites
• This is the modern form of the
metric system and is generally a
system of units of measurement
devised around seven base units
and the convenience of the number
ten.
• It is the world's most widely used
system of measurement, both in
everyday commerce and in science.
9.
Advantages of SI over the English System
• More consistent measuring tools
• Extensively used in science and
other related fields
• Easier to convert units within the
system
10.
SI Fundamental Quantities
Quantity
Unit (Symbol)
Mass (m)
kilogram (kg)
Time (T)
seconds (s)
Length (l)
meter (m)
Temperature (T)
kelvin (K)
Amount of Substance (n)
mole (mol)
Luminous Intensity (I)
candela (cd)
Current (I)
ampere (A)
11.
Conversion within the SI
What makes conversion
between SI units is its
extensive use of prefixes
instead of arbitrary
12.
SI Prefixes and Equivalents
SI Prefixes and Equivalents
Power of Ten
Prefix
Symbol
Power of Ten
Prefix
Symbol
1024
yotta
zetta
exa
Y
Z
E
10-1
deci
centi
milli
d
c
m
peta
tera
giga
P
T
G
micro
nano
pico
μ
n
p
mega
kilo
hecto
deca
M
k
h
da
femto
atto
zepto
f
a
z
yocto
y
1021
1018
1015
1012
109
106
103
102
101
10-2
10-3
10-6
10-9
10-12
10-15
10-18
10-21
10-24
13.
Conversion within the SI
Time:
1 hour (hr) = 60 minutes (min)
1 minute = 60 seconds (s)
time intervals shorter than a
second uses the metric
prefixes (e.g. ms, μs, ps)
14.
Conversion within the SI
Temperature:
K = °C + 273.15
°C = K – 273.15
15.
Conversion between English and SI
1 inch = 2.54 cm
2.2 lbs = 1 kg
°F = 9/5 °C + 32
°C = 5/9 (°F – 32)
Metric units:
1 liter (L) = 1 000 milliliter (mL)
1 mL = 1cm3
1000 L = 1 m3
17.
Convert the following observing proper
units and correct number of significant
figures.
1.
2.
3.
4.
5.
125 m ? Km
20.0 cm ? In
160 mi ? Km
25 kg ? Lbs
1560 mg ? kg
18.
TEMPERATURE
• The degree of the hotness or the
coldness of a body (layman).
• The measure of the average kinetic
energy of the particles of a body.
19.
The Temperature Scales
• The Fahrenheit Scale - based on 32
for the freezing point of water and
212 for the boiling point of water
• The scale is divided into 180 equal
intervals
• Dwveloped in the 18th-century by
the German physicist Daniel Gabriel
Fahrenheit
20.
The Temperature Scales
• The Celsius Scale – also called the
centigrade scale
• Based on 0 for the freezing point of
water and 100 for the boiling point
of water
• Invented in 1742 by the Swedish
astronomer Anders Celsius
21.
The Temperature Scales
• The Kelvin Scale - the base unit of
thermodynamic temperature
measurement in the International System
(SI) of measurement
• An absolute temperature scale named for
the British physicist William Thomson
Baron Kelvin
• Its zero point is in absolute zero, the
theoretical temperature at which the
molecules of a substance have the lowest
energy
22.
Conversion (oF and oC)
• F = 9/5C + 32
• C = 5/9(F - 32)
23.
Conversion (oF and K)
• C = K - 273
• K= C + 273
24.
Seatwork: ½ Pad Paper
1. 56.0 oC oF K
2. 89 oF oC K
3. Find the temperature at which the
reading in both the oF Scale and the oC
Scale is the same? Show your solution.
4. Explain or discuss the 2004 definition
of MEASUREMENT in not more than 5
sentences.
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