Physical quantities
Physical quantities are divided into two groups
(a) Fundamental quantities
These are physical quantities which cannot be expressed in form
of other quantities using any mathematical equations. They
include
Quantity S.I unit Symbol of S.I unit
Mass kilogram kg
Time second s
Length metres m
Temperature Kelvin K
Current Ampere A
(b) Dimensional/derived quantities
These are physical quantities which can be expressed in terms of fundamental quantities.
For example velocity, work, volume, density
Dimensions of physical quantities
This is a way in which derived quantities can be expressed in form of fundamental
quantities. i.e.
Mass- M
Length- L
Time –T
The square bracket, [ ] is used to show dimensions
For example
(i) [Area] = length x length or length x width
L x L = L2
(ii) Volume = length x width x height
= L x L x L = L3
(iii) Density = [ ] = or ML-3
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Physical quantities are divided into two groups
(a) Fundamental quantities
These are physical quantities which cannot be expressed in form
of other quantities using any mathematical equations. They
include
Quantity S.I unit Symbol of S.I unit
Mass kilogram kg
Time second s
Length metres m
Temperature Kelvin K
Current Ampere A
(b) Dimensional/derived quantities
These are physical quantities which can be expressed in terms of fundamental quantities.
For example velocity, work, volume, density
Dimensions of physical quantities
This is a way in which derived quantities can be expressed in form of fundamental
quantities. i.e.
Mass- M
Length- L
Time –T
The square bracket, [ ] is used to show dimensions
For example
(i) [Area] = length x length or length x width
L x L = L2
(ii) Volume = length x width x height
= L x L x L = L3
(iii) Density = [ ] = or ML-3
Sponsored by The Science Foundation College 0753 80 27 09 Join Now
