Second and third class levers are differentiated by __________.

Second and third class levers are differentiated by their arrangement of the load, effort, and the fulcrum.

1. Fulcrum Position: In a second class lever, the fulcrum is located at one end of the lever, with the load in the middle and the effort applied at the other end. This setup allows for a mechanical advantage, as the effort arm is longer than the load arm. A common example of a second class lever is a wheelbarrow, where the wheel acts as the fulcrum.

2. Effort Position: In a third class lever, the fulcrum is also at one end, but the effort is applied between the fulcrum and the load. This configuration does not provide a mechanical advantage because the load arm is longer than the effort arm, requiring more effort to lift the load. A common example of a third class lever is a pair of tweezers, where the user's grip applies force to the middle of the lever, while the load is at the opposite end.

Thus, the main differentiation lies in the position of the effort in relation to the load and fulcrum.