Mechanical Systems

• Mechanism


  Devices that change the magnitude and direction of force
• Levers


  • Mechanisms that move and lift loads by rotating around a stationary point
• Linkages


  • When multiple levers are connected together
• Gears


  • Toothed wheels that interlock
• Rotary systems


  • Mechanical systems that use rotary motion
• Mechanical advantage


  Using mechanisms to make something easier to do
• Types of motion


  • Reciprocating
  • Oscillating
  • Rotary
  • Linear
• Reciprocating motion


  Moving backwards and forwards in a straight line
• Oscillating motion


  Moving backwards and forwards in an arc
• Rotary motion


  Moving in a circle
• Linear motion


  Moving one way in a straight line
• Devices with reciprocating motion

  • Sewing machine
• Devices with oscillating motion

  • Swings
• Devices with rotary motion


  • Wheels
  • Train
• Types of levers


  • First order lever
  • Second order lever
  • Third order lever
• First order lever


  • Move the pivot closer to the load to make it easier to lift
• Second order lever


  • Move the pivot and load closer together to make it easier to lift
• Third order lever


  • Move the effort and pivot further apart to make it easier to lift
• Devices with third order levers

  • Food tongs
• Devices with second order levers

  • Wheelbarrow