
Quantities & Units 
Here are a selection of quantities that you will have met:
Quantity  Symbol  Unit 

mass  m  kilogram, kg 
distance  d  metre, m 
time  t  second, s 
current  I  amp, A 
voltage  V  volts, V 
resistance  R  ohm, 
force  F  newton, N 
area  A  squaremetre, m² 
energy  E or W  joule, J 
power  P  watt, W 
Use the symbol when writing an equation.
Use the unit when describing how much of something there is.
