2.2.A—Describe a force as an interaction between two objects or systems

Describe a force as an interaction between two objects or systems.

• Forces are vector quantities that describe the interactions between objects or systems.
  • i. A force exerted on an object or system is always due to the interaction of that object with another object or system.
  • ii. An object or system cannot exert a net force on itself.
• Contact forces describe the interaction of an object or system touching another object or system and are macroscopic effects of interatomic electric forces. TOPIC 2.2 Forces and Free-Body Diagrams