Contact and Non-Contact forces

• Define what a force is.

  A force is a push or pull, that acts on an object, due to its interaction with another object
• What is force measured in?

  Newtons (N)
• Is force a vector or scalar quantity? why?

  Force is a vector quantity because it has magnitude and direction
• What are the 2 different types of forces?

  • contact force
  • non-contact force
• What is a contact force?

  when 2 objects have to be physically touching for a force to act
• What is a non-contact force?

  When two objects do not need to be touching in order for a force to act
• What are the 4 main contact forces?

  • Friction
  • Air resistance
  • Normal contact force
  • Tension
• What are the 3 main non-contact forces?

  • Gravitational force
  • Magnetic force
  • Electrostatic force
• Why is air resistance classed as a contact force?

  Air resistance happens due to the physical contact (collisions) between an object and air particles
• What are interaction pairs?

  An interaction pair is a pair of forces that are equal and opposite and act on 2 interacting objects
• What 2 planets are examples of interaction pairs and are attracted to each other due to gravitational force?

  The sun and The earth