| Questions | 5 |
| Topics | Bridge Forms, Normal Force, Normal Force vs. Weight, Third-Class Lever, Work-Energy Theorem |
The six basic bridge forms are beam, truss, arch, cantilever, cable, and suspension.
Normal force (FN) represents the force a surface exerts when an object presses against it.
Normal force arises on a flat horizontal surface in response to an object's weight pressing it down. Consequently, normal force is generally equal to the object's weight.
A third-class lever is used to increase distance traveled by an object in the same direction as the force applied. The fulcrum is at one end of the lever, the object at the other, and the force is applied between them. This lever does not impart a mechanical advantage as the effort force must be greater than the load but does impart extra speed to the load. Examples of third-class levers are shovels and tweezers.
The work-energy theorem states that the work done by the sum of all forces acting on a particle equals the change in the kinetic energy of the particle. Simply put, work imparts kinetic energy to the matter upon which the work is being done.