3. CHAPTER II: Measurements and Scientific Notations
Learning Outcome 1:
Explain the concept of
measurement and scientific
notation.
4. Measurement is the assignment of a number to a
characteristic of an object or event, which can be compared with other
objects or events using measuring devices or tools.
There are two acceptable systems of measure that are used
internationally, the Metric (SI) and the English system. The basic units of
measurements in the metric system are Meter (m) for linear, Gram (g) for
weight and Liter (L) for volume. The English system uses inch, foot, and
the yard in measuring length.
CHAPTER II: Measurements and Scientific Notations
5. THE METRIC SYSTEM OF MEASUREMENTS
LENGTH
millimeter (mm)
1 centimeter =10mm
1 decimeter =100mm =10cm
1 meter =1000mm =100cm =10dm
1 dekameter =10000mm =1000cm =100dm = 10m
1 hectometer =100000mm =10000cm =1000dm = 100m =10dkm
1 kilometer =1000000mm =100000cm =10000dm =1000m =100dkm =10hm
WEIGHT VOLUME TIME
milligram milliliter seconds
centigram centiliter 1 minute = 60 seconds
decigram deciliter 1 hour = 60 minutes
gram liter 1 day = 24 hours
dekagram dekaliter 1 week = 7 days
hectogram hectoliter 1 month = 30 days
kilogram kiloliter 1 year = 365 days
CHAPTER II: Measurements and Scientific Notations
6. THE METRIC SYSTEM OF MEASUREMENTS
MEASURABLE QUANTITIES UNIT ABREVIATION
Acceleration meter per second squared m/s2
Amount of substance Mole mol
Angle Radian R
Angular Acceleration radian per second squared r/s2
Angular Velocity radian per second r/s
Area square meter m2
Density kilogram per cubic meter kg/m3
Electrical Current Ampere A
Energy Joule J or N-m
Force Newton N or kg-m/s2
Frequency Hertz Hz or 1/s
Impulse Newton-second kg-m/s
CHAPTER II: Measurements and Scientific Notations
7. THE METRIC SYSTEM OF MEASUREMENTS
MEASURABLE
QUANTITIES
UNIT ABREVIATION
Length Meter M
Luminous intensity Candela cd
Mass Kilogram kg
Moment of a Force Newton-meter N-m
Power Watt W or J/s
Pressure Pascal Pa or N/m2
Stress Pascal Pa or N/m2
Temperature Kelvin K
Time Second S
Velocity meter per second m/s
Volume (solids) cubic meter m3
Volume (liquids) Liter L or 10-3
m3
Work Joule J or N-m
CHAPTER II: Measurements and Scientific Notations
9. SCIENTIFIC NOTATION
A real number x is said to be expressed in scientific notation if it is written
in the form x = ± a.b × 10n, where n is an integer and 1 ≤ a ≤ 9 and b is a
decimal number or zero. The integer n is called the characteristic of x, the
number a.b is called the mantissa of x, and the factor 10n is called the order
of magnitude of x.
To change a number from ordinary decimal form to scientific notation,
move the decimal point to obtain a number between 1 ≤ x < 10 and multiply
by 10n or by 10–n , where n is the number of times the point moved to the
left or to the right.
CHAPTER II: Measurements and Scientific Notations
10. NAMES AND SCIENTIFIC PREFIXES FOR SOME
INTEGER POWERS OF 10
Let us consider the number of electrons passing by a point in a circuit every second with a steady
electric current of 1 amp: 1 amp = 6,250,000,000,000,000,000 electrons per second. This can be
change to scientific notation by moving the decimal point 18 places to the left to obtain
6.250,000,000,000,000,000 and multiply it by 1018, so that 6,250,000,000,000,000,000 =6.25×1018
electron per second. Another example is the Proton mass = 0.000 000 000 000 000 000 000 00167
grams. To change it to scientific notation, we move the decimal point 25 places to the right to obtain
1.67 then multiply it by 10–25, so that we have 1.67×10–25 grams.
CHAPTER II: Measurements and Scientific Notations
11. NAMES AND
SCIENTIFIC
PREFIXES
FOR SOME
INTEGER
POWERS OF
10
Power of 10 Names Numeral Prefix Abbreviation
1018
Quintillion 1,000,000,000,000,000,000 Exa E
1015
Quadrillion 1,000,000,000,000,000 Peta P
1012
Trillion 1,000,000,000,000 Tera T
109
Billion 1,000,000,000 Giga G
106
Million 1,000,000 Mega M
103
Thousand 1,000 Kilo k
102
Hundred 100 Hecto h
101
Ten 10 Deka da
100
Unit 1
10–1
Tenth 0.1 Deci d
10–2
Hundredth 0.01 Centi c
10–3
Thousandth 0.001 Milli m
10–6
Millionth 0.000 001 Micro µ
10–9
Billionth 0.000 000 001 Nano n
10–12
Trillionth 0.000 000 000 001 Pico p
10–15
Quadrillionth 0.000 000 000 000 001 Femto f
10–18
Quintillionth 0.000 000 000 000 000 001 Atto A
CHAPTER II: Measurements and Scientific Notations