2.1.2 Second-class levers

• In a second-class lever, the fixed point around which the lever rotates is called the fulcrum
• A third-class lever system has the effort located between the fulcrum and the load.
• Describe the arrangement of a second-class lever in terms of fulcrum, load, and effort.

  Fulcrum at one end
• What is the role of the fulcrum in a lever system?

  Fixed point of rotation
• What does the load represent in a second-class lever?

  The resistance being moved
• In lifting the body on the toes, the ankle joint acts as the fulcrum
• In lifting the body on the toes, the calf muscles provide the effort
• In a second-class lever, the effort force is less than the load force, but the effort moves a greater distance.


  True
• The fulcrum in a second-class lever is always located at one end of the system.


  True
• In a second-class lever, where is the load positioned?

  Between fulcrum and effort
• In a second-class lever, the fulcrum is the fixed point around which the lever rotates
• In the example of lifting the body on the toes, the calf muscle contraction provides the effort
• What is the formula for mechanical advantage in a second-class lever?

  Distance from fulcrum to effort / Distance from fulcrum to load
• Order the components of mechanical advantage in a second-class lever from greatest to least in lifting the body on the toes:

  1️⃣ Distance from fulcrum to effort

  2️⃣ Mechanical advantage

  3️⃣ Distance from fulcrum to load
• The toe raise during a gymnastics routine is an example of a second-class lever.


  True
• Lifting the body on the toes is an example of a second-class lever system.

  True
• What is the term for the resistance or weight being moved in a lever system?

  Load
• In a first-class lever, the fulcrum is located between the load and the effort.
• What is the position of the fulcrum in a second-class lever?

  At one end
• The effort in a second-class lever is the force applied to move the load.


  True
• In a second-class lever, the load is positioned between the fulcrum and the effort.


  True
• When opening a door, the hinges act as the fulcrum in a second-class lever.


  True
• When lifting the body on the toes, the ankle joint serves as the fulcrum
• What is an example of a first-class lever system?

  Seesaw
• The effort in a second-class lever is applied at the end opposite the fulcrum.


  True
• In a second-class lever, the fulcrum is always located at one end.


  True
• The positions of the fulcrum, load, and effort vary across different lever systems.

  True
• In a second-class lever, the effort force is less than the load force.
• What is the fulcrum in the example of pushing a wheelbarrow?

  Wheel of the wheelbarrow
• What is the definition of a second-class lever system?

  Fulcrum between load and effort
• Where is the fulcrum located in a first-class lever system?

  Between load and effort
• The effort in a second-class lever system is the force applied to move the load.


  True
• Opening a door is an example of a second-class lever with the hinges as the fulcrum.


  True
• The fixed point around which the lever rotates is called the fulcrum
• What is an example of a second-class lever in the human body?

  Lifting on toes
• Where is the load located in relation to the fulcrum and effort in a second-class lever?

  Between fulcrum and effort
• What is the formula for mechanical advantage in a second-class lever?

  $MA =$$\frac{\text{Fulcrum to effort}}{\text{Fulcrum to load}}$
• What acts as the fulcrum when opening a door in a second-class lever system?

  Hinges
• When lifting the body on the toes, the calf muscles provide the effort
• What is the fulcrum in the example of lifting the body on the toes?

  Ankle joint