levers

• • the most basic form of a machine which helps lift a heavy object with alot less effort
  • a lever is a rigid bar that rotates around a fulcrum to apply a force to a load
• 1,2,3 F,L,E
• lever


  bone
• fulcrum


  joint
• effort


  muscular force
• load


  weight/ resistance
• class 1

  • mechanical advantage or mechanical disadvantage depending how close the fulcrum is to the effor or the load
  • tricep extension
  • head
• class 2

  • mechanical advantage so the load can be lifted easier or you can lift a bigger load with less effort
  • standing heel lift
  • plantar flexion
• class 3

  • mechanical disadvantage so it requires more effort to lift the load
  • bicep curl
  • dorsiflexion
  • knee extension
• mechanical advantage


  the ability to lift a heavy load with minimal effort
• Mechanical advantage = effort arm ÷ weight (resistance) arm.