Which of the following best describes a class 3 lever?

A class 3 lever is defined by its arrangement, where the effort (force) is applied between the load (resistance) and the fulcrum (pivot point). In the context of the options provided, elbow flexion is an excellent example of a class 3 lever system.

When you flex your elbow, the fulcrum is the elbow joint, the effort is applied by the biceps muscle as it contracts, and the load is the weight of the forearm and anything being held in the hand. This configuration effectively illustrates the characteristics of a class 3 lever, as the effort is indeed applied between the fulcrum and the load, allowing for a range of motion and speed of movement.

In comparison, the other options do not represent this lever type accurately. For example, standing on the balls of your feet involves a class 2 lever situation where the load (body weight) is between the fulcrum (the ball of the foot) and the effort (force exerted by the calf muscles). On the other hand, a seesaw or nodding your head back and forth represents a class 1 lever, where the fulcrum is located between the effort and the load. Lastly, the function of the