Levers

• What does the human body act as in terms of mechanics?

  A complex system of levers
• What are the components of the lever system in the human body?

  Bones serve as rigid bars, joints as pivot points, and muscles provide the effort
• What are the three classes of levers in the human body?

  1. First-Class Levers
  2. Second-Class Levers
  3. Third-Class Levers
• Where is the fulcrum located in a first-class lever?

  The fulcrum is located between the effort and the load
• Give an example of a first-class lever in the human body.

  Extending the neck to head a football
• In a second-class lever, where is the load located?

  The load is located between the fulcrum and the effort
• What is an example of a second-class lever in the human body?

  Standing on tiptoes (plantar flexion)
• Where is the effort located in a third-class lever?

  The effort is located between the fulcrum and the load
• Provide an example of a third-class lever in the human body.

  Flexing the elbow during a bicep curl
• What is Mechanical Advantage (MA) in a lever system?

  • MA occurs when the effort arm is longer than the load arm
  • Allows a smaller effort to move a larger load
• What is Mechanical Disadvantage (MD) in a lever system?

  • MD occurs when the effort arm is shorter than the load arm
  • Requires greater effort to move a load
  • Allows for greater speed and range of motion
• How does the javelin thrower's arm function as a lever system?

  It acts as a third-class lever with a mechanical disadvantage
• What does the mechanical disadvantage in the javelin throw allow for?

  It allows the javelin to be thrown with greater speed and distance
• How does rowing utilize lever systems?

  Rowing involves second-class levers with the oarlock as the fulcrum
• What is the role of the oarlock in rowing?

  The oarlock acts as the fulcrum in the lever system
• How does cycling utilize lever systems?

  Cycling utilizes both second and third-class levers
• What is the function of the pedal system in cycling?

  The pedal system functions as a second-class lever
• What does the leg extension at the knee joint prioritize in cycling?

  It prioritizes speed and range of motion for efficient pedalling