A bearing or other device is needed to hold the beam in ________ lever/levers.

Key Points

• In Class 1 and Class 3 levers, the fulcrum or the force is located at one end, requiring support like a bearing or pivot to hold the beam in place.
• Class 1 lever has the fulcrum between the effort and the load (e.g., seesaw), which must be held with a pivot/bearing.
• Class 3 lever has the effort between the fulcrum and the load (e.g., tweezers), also requiring support to stabilize the beam.
• These types of levers need a fixed point or axis of rotation, which is typically provided by a bearing, hinge, or other support.
• Class 2 levers do not usually require a bearing to stabilize the beam in the same way, as the load lies between the effort and fulcrum (e.g., wheelbarrow).

Additional Information

• Class 1 Lever:
  • Fulcrum between load and effort.
  • Examples: Seesaw, scissors, crowbar.
  • Can multiply force or speed depending on fulcrum position.
• Class 2 Lever:
  • Load between effort and fulcrum.
  • Examples: Wheelbarrow, nutcracker.
  • Always multiplies force; mechanical advantage > 1.
• Class 3 Lever:
  • Effort between fulcrum and load.
  • Examples: Tweezers, tongs, human forearm.
  • Multiplies speed and distance; mechanical advantage < 1.
• Role of Bearings:
  • Bearings provide rotational support to the lever beam, minimizing friction.
  • Essential in systems where a stable pivot point is necessary.
• Mechanical Advantage:
  • Levers provide mechanical advantage by trading force for distance or vice versa.