First class levers and equilibrium positions

• To study the first-class levers
• To understand and verify equilibrium of a balance

A first-class lever is a lever in which the fulcrum is located between the input effort and the output load. In operation, a force is applied (by pulling or pushing) to a section of the bar, which causes the lever to swing about the fulcrum, overcoming the resistance force on the opposite side. The fulcrum may be at the center point of the lever as in a seesaw or at any point between the input and output. This supports the effort arm and the load.

This simple machine is said to provide no mechanical advantage if the arms of the lever measure the same length. If the arm length of the power is bigger than that of the resistance we have a simple machine with mechanical advantage.

When we talk about levers, we must introduce the concept of moment of a force.

• Cylindrical masses with hook (50, 25, 10 g) — 4111.08-10-12
• Lever holed rod with pair of threaded cylinders — 4114.13
• Rod with threaded stem M3, diam. 8 mm, length 70 mm — 4861.10-021
• “S” hooks, length 30 mm — 4113.35
• Multifunction support rod, rounded ends, with holes, length 350 mm — 5408.91