Quantities, units and symbols
It is most important that when you write down a quantity you give it the correct units
and use the correct symbol for those units. The following table shows most of the
common quantities.
Quantity measured |
Name of unit |
Symbol of unit |
Length (L) |
metre |
m |
Mass (m) |
kilogram |
kg |
Time (t) |
second |
s |
Velocity (v) |
metres per second |
m/s |
Acceleration (a) |
metres per second per second |
m/s2 |
Momentum |
newton second |
Ns |
Force (F) |
newton |
N |
Energy |
joule |
J |
Power |
watt |
W |
Density (ρ) |
kilograms per metre cube |
kg/m3 |
Pressure (P) |
Pascal, newtons per square metre |
Pa, N/m2 |
Frequency (f) |
hertz |
Hz |
Temperature |
degrees centigrade, kelvin |
oC, K |
Specific heat capacity |
joules per kilogram per oC |
J/kgoC |
Specific latent heat |
joules per kilogram |
J/kg |
Charge (Q) |
coulomb |
C |
Current (I) |
amp, ampere |
A |
Voltage (V) |
volt |
V |
Potential difference (p.d) |
volt |
V |
Resistance (R) |
ohm |
Ω |
A VERSION IN WORD IS AVAILABLE ON THE SCHOOLPHYSICS CD