The following tables list some common physical, mechanical, and electrical quantities, along with their units and the corresponding symbols.
General Physical Quantities: These quantities are widely used in physics, mechanical engineering, electrical engineering, and other fields.
Quantity  Symbol  Unit  Symbol for the Unit 
acceleration  a  meters per second per second  m/s^{2} 
angle  θ or φ  radian  rad 
degree  °  
angular frequency  ω  radians per second  rad/sec 
energy  W  joule  J 
force  F  newton  N 
pound  lb  
mass  m  kilogram  kg 
period  T  second  s 
power  P  watt  W 
time  t  second  s 
velocity  v  meters per second  m/s 
miles per hour  mph 
Mechanical Quantities: These quantities are used in statics, dynamics, strength of materials, and other areas studied by mechanical engineers.
Quantity  Symbol  Unit  Symbol for the Unit 
bending moment  M  pound inch  lb·in 
newton meter  N·m  
distributed load  q  pounds per inch  lb/in 
newtons per meter  N/m  
elastic modulus (also called Young's modulus)  E  pounds per square inch  lb/in^{2} 
newtons per square meter  N/m^{2}  
flexural rigidity  EI  pound inches squared  lb·in^{2} 
newton meters squared  N·m^{2}  
normal stress 

pounds per square inch  lb/in^{2} 
newtons per square meter  N/m^{2}  
second moment of area  I  inches to the fourth  in^{4} 
meters to the fourth  m^{4}  
shear force  V  pound  lb 
newton  N  
shear stress 

pounds per square inch  lb/in^{2} 
newtons per square meter  N/m^{2}  
spring rate  k  newtons per meter  N/m 
tension  T  newton  N 
pound  lb  
weight  W  newton  N 
pound  lb 
Electrical Quantities: These quantities are used in circuit analysis and other areas studied by electrical engineers.
Quantity  Symbol  Unit  Symbol for the Unit 
capacitance  C  farad  F 
charge  Q  coulomb  C 
current  I  ampere  A 
impedance  Z  ohm  Ω 
inductance  L  henry  H 
reactance  X  ohm  Ω 
resistance  R  ohm  Ω 
voltage  V  volt  V 