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 (speed) (v) |
metres per second |
m/s |
| Acceleration (a) |
metres per second per second |
m/s2 |
| Momentum (M) |
newton second |
Ns |
| Force (F) |
second |
s |
| Energy (E) |
joules |
J |
| Work |
metre |
m |
| Power (P) |
kilogram |
kg |
| Density (r |
second |
s |
| Pressure |
pascals |
Pa |
| Frequency (f) |
hertz |
Hz |
| Temperature |
degrees C, Kelvin |
o, K |
| Specific heat capacity |
joules per kilogram per oC |
J/kgoC |
| Specific latent heat |
joules per kilogram |
J/kg |
| Charge (Q) |
coulombs |
C |
| Current (I) |
amperes (amps) |
A |
| Voltage (V) |
volts |
V |
| Potential difference |
volts |
V |
| Resistance (R) |
ohms |
W |
