Contact & Non-contact Forces

• contact forces

  where objects must be touching in order to experience a force
• non-contact forces

  where objects do not need to touch in order to experience a force
• vectors

  have a magnitude and direction
• scalar

  only has a magnitude
• examples of vector quantities

  • force
  • velocity
  • displacement
  • weight
• examples of scalar quantities

  • speed
  • distance
  • mass
  • temperature
  • time
• contact forces

  • friction
  • air resistance
  • upthrust
• non-contact forces

  • magnetic force
  • gravitational force
  • electrostatic force
• weight

  is the force acting on an object
• mass

  amount of stuff in an object
• weight = mass x gravitational field strength
• mass and weight are directionally proportional
• resultant force

  the overall force on a point or object
• when a force moves an object through a distance energy is transferred and work done is on the object
• work done = force x distance