Final answer:
The fulcrum is the fixed point at which a lever pivots, and it's fundamental in lever mechanics, affecting the force needed and mechanical advantage.
Step-by-step explanation:
The point at which the lever pivots is known as the fulcrum. In the context of levers, a lever is a rigid bar that rotates about a fixed point when a force is applied. It's important for understanding the mechanical advantage, as the distance from the fulcrum influences the force required to lift an object. The larger the distance from the fulcrum to where the force is applied (the lever arm), the less force is needed to lift an object on the other side. Conversely, the mass of the object being lifted, the length of the lever on both sides of the fulcrum, and the location where the force is applied all play a critical role in the effectiveness of a lever.