Wheel and axle. The wheel and axle is one of six simple machines identified by Renaissance scientists drawing from Greek texts on technology. The wheel and axle consists of a wheel attached to a smaller axle so that these two parts rotate together in which a force is transferred from one to the other.
The San Andreas Fault is the sliding boundary between the Pacific Plate and the North American Plate. It slices California in two from Cape Mendocino to the Mexican border. San Diego, Los Angeles and Big Sur are on the Pacific Plate. San Francisco, Sacramento and the Sierra Nevada are on the North American Plate. And despite San Franciscoâs legendary 1906 earthquake, the San Andreas Fault does not go through the city.
Situated at the boundary to the San Gabriel Valley and San Fernando Valley, the Sierra Madre Fault Zone (also known as the Sierra Madre-Cucamonga Fault ) runs along the southern edge of the San Gabriel Mountains for a total of 95 kilometers (59 mi), where the northwesternmost 19 km (12 mi) comprises the San Fernando Fault (the section responsible for the 1971 San Fernando earthquake ).