constraint (mechanics)
{{short description|Parameter which a physical system must obey}}
In classical mechanics, a constraint on a system is a parameter that the system must obey. For example, a box sliding down a slope must remain on the slope. There are two different types of constraints: holonomic and non-holonomic.{{Cite book|title=Molecular Modelling: Principles and Applications|last=Leach|first=Dr Andrew|date=2001-01-30|publisher=Prentice Hall|isbn=9780582382107|edition= 2nd|location=Harlow|pages=369–370|language=en}}
Types of constraint
- First class constraints and second class constraints
- Primary constraints, secondary constraints, tertiary constraints, quaternary constraints
- Holonomic constraints, also called integrable constraints, (depending on time and the coordinates but not on the momenta) and Nonholonomic system
- Pfaffian constraints
- Scleronomic constraints (not depending on time) and rheonomic constraints (depending on time)
- Ideal constraints: those for which the work done by the constraint forces under a virtual displacement vanishes.