Contact and Non-Contact Forces

• What are the two types of forces mentioned?

  Contact and non-contact forces
• How is a vector represented?

  By an arrow showing magnitude and direction
• What is the difference between speed and velocity?

  Speed is scalar; velocity is vector
• What is a contact force?

  A force that requires touching objects
• What is a non-contact force?

  A force that does not require touching
• What is an interaction pair?

  A pair of equal and opposite forces
• How does Newton's Third Law relate to interaction pairs?

  It states forces are equal and opposite
• What happens when two objects interact?

  A force is produced on both objects
• What force acts between the Sun and the Earth?

  Gravitational force
• How do the Sun and Earth interact gravitationally?

  They attract each other with equal forces
• What is the normal contact force?

  A force exerted by a surface against an object
• How does a chair interact with the ground?

  The chair pushes down; the ground pushes up
• What are the characteristics of contact and non-contact forces?

  • Contact Forces:
  • Require touching objects
  • Examples: friction, tension
  • Non-Contact Forces:
  • Do not require touching
  • Examples: gravitational, magnetic
• What are the implications of Newton's Third Law in interactions?

  • Forces are equal and opposite
  • Action and reaction forces occur simultaneously
  • Both objects experience the same magnitude of force