1.1 - Quantities and units
Système International (SI) units (base units)
●
Base quantity Base unit
Name Typical symbol Name Symbol
time t second s
length x, metre m
s (displacement)
mass m kilogram kg
electric current I ampere A
thermodynamic T kelvin K
temperature
amount of n mole mol
substance
luminous intensity lv candela cd
● Derived units
Quantity Name of unit Symbol Base units Derivation equations
area square metre A m2 A=L(length[m]) ×W ( width[m])
volume cubic metre V m3 V = A (area[m2 ])× H (width [m])
mass per µ kg m-1
unit length
mass per σ kg m-2
unit area
density kilogram per ρ kg m-3 m(mass [kg])
cubic metre ρ= 3
V (volume [m ])
velocity metres per v m s-1 s (distance [m])
second v=
t(time [s])
acceleration metres per a m s-2 v ( speed / velocity [m/ s])
second a=
t (time [s ])
squared
momentum p kg m s-1 p=m( mass[kg]) × v (velocity [m/s])
1
Système International (SI) units (base units)
●
Base quantity Base unit
Name Typical symbol Name Symbol
time t second s
length x, metre m
s (displacement)
mass m kilogram kg
electric current I ampere A
thermodynamic T kelvin K
temperature
amount of n mole mol
substance
luminous intensity lv candela cd
● Derived units
Quantity Name of unit Symbol Base units Derivation equations
area square metre A m2 A=L(length[m]) ×W ( width[m])
volume cubic metre V m3 V = A (area[m2 ])× H (width [m])
mass per µ kg m-1
unit length
mass per σ kg m-2
unit area
density kilogram per ρ kg m-3 m(mass [kg])
cubic metre ρ= 3
V (volume [m ])
velocity metres per v m s-1 s (distance [m])
second v=
t(time [s])
acceleration metres per a m s-2 v ( speed / velocity [m/ s])
second a=
t (time [s ])
squared
momentum p kg m s-1 p=m( mass[kg]) × v (velocity [m/s])
1
