System

Definition

A system is a defined collection of objects considered for analysis. It separates the objects of interest from the environment to study forces and motion.

5 Must Know Facts For Your Next Test

1. In Newton's second law, a system helps identify which forces act on the objects being studied.
2. Internal forces within a system do not affect the net force or acceleration of the system.
3. The boundary of a system is arbitrary and can be chosen to simplify problem-solving.
4. External forces acting on a system determine its acceleration according to $F = ma$.
5. Choosing an appropriate system can make it easier to apply Newton's laws and solve dynamics problems.

Review Questions

• What role does a system play in applying Newton’s second law?
• Why are internal forces within a system typically ignored when calculating net force?
• How do external forces influence the acceleration of a system?

Related terms

External Force:

A force that acts on an object or system from outside its defined boundaries.

Net Force:

The vector sum of all external forces acting on a system, determining its acceleration.

Acceleration: $\text{The rate of change of velocity of an object, directly proportional to net force and inversely proportional to mass}$.