Physical quantities can be measured and consist of a numerical magnitude and unit. There are base quantities like length, mass, and time that are not combined with other quantities, and there are derived quantities that are a combination of two or more base quantities, like volume or velocity. Quantities can be scalars that only have magnitude, or vectors that have both magnitude and direction.
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Physical quantities can be measured and consist of a numerical magnitude and unit. There are base quantities like length, mass, and time that are not combined with other quantities, and there are derived quantities that are a combination of two or more base quantities, like volume or velocity. Quantities can be scalars that only have magnitude, or vectors that have both magnitude and direction.
Physical quantities can be measured and consist of a numerical magnitude and unit. There are base quantities like length, mass, and time that are not combined with other quantities, and there are derived quantities that are a combination of two or more base quantities, like volume or velocity. Quantities can be scalars that only have magnitude, or vectors that have both magnitude and direction.
Copyright:
Attribution Non-Commercial (BY-NC)
Available Formats
Download as PPT, PDF, TXT or read online from Scribd
Physical quantities can be measured and consist of a numerical magnitude and unit. There are base quantities like length, mass, and time that are not combined with other quantities, and there are derived quantities that are a combination of two or more base quantities, like volume or velocity. Quantities can be scalars that only have magnitude, or vectors that have both magnitude and direction.
Copyright:
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Download as PPT, PDF, TXT or read online from Scribd
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Physical Quantity
A quantity that can be measured and consists of a numerical magnitude and a unit.
Physical Quantity
Base Quantity A unit that is not combined with one another or more physical quantities.
Derived Quantity A combination of two or more base quantities.
Base Quantities Base Quantity Length Symbol SI Unit Metre Symbol for the unit
Mass Time
Temperature Electrical current
l m t T I
Kilogram Second
kg s
Kelvin ampere
K A
Derived Quantity A combination of two or more base quantities. Physical quantity Volume Velocity Density Force Electric charge Symbol Relation with base quantity Length (m) X Length (m) X Length(m) Displacement (m) / Time (s) Mass (kg) / Volume (m3) Mass (kg) X Acceleration (m s-2) Current (ampere) X time (s) Formula V = l3 v = s/t = m/V F = ma Q = It SI units m3 ms -1 kg m-3 N C
V v
F Q
The values of measurement in scientific studies normally involve numbers that are either very large or very small.
Such number are difficult to record or to read off.
Speed of light: =300 000 000 ms-1 The distance between the Sun and Mars =227 800 000 000 m
Scientific Notation The form in the scientific notation is
M 10 300000000 ms
Standard form
3 10 3.2 10
8 11
0.000000000032m
Prefixes Prefixes are used in the metric system to indicate fractions or multiples of SI units. For measurement whose magnitude is very large, prefixes such as kilo, Mega, Giga and Tera are used.
For measurement whose magnitude is very small, prefixes such as centi, milli, micro, nano and pico are used.
Prefixes Prefix TeraSymbol T Standard Form 1012 Example Terametre (Tm)
GigaMegakilohecto-
G M k h
109 106 103 102
Gigabyte (GB) Megawatt (MW) Kilometre (km) Hectometre (hm)
