Lever force F at a point "A" located by the coordinate vector r on the bar. The lever then exerts an output force F at the point "B" located by r. The rotation of the lever about the fulcrum "P" is defined by the rotation angle "θ" in radians. Let the coordinate vector of the point "P" that defines the fulcrum be r, and introduce the lengths which are the distances from the fulcrum to the input point "A" and to the output point "B", respectively. Now introduce the unit vectors e and e from the fulcrum to the point "A"
Lever of the lever. The word "lever" entered English about 1300 from Old French, in which the word was "levier". This sprang from the stem of the verb "lever", meaning "to raise". The verb, in turn, goes back to the Latin "levare", itself from the adjective "levis", meaning "light" (as in "not heavy"). The word's primary origin is the Proto-Indo-European (PIE) stem "legwh-", meaning "light", "easy" or "nimble", among other things. The PIE stem also gave rise to the English word "light". The earliest remaining writings regarding levers date from the 3rd century BCE and were provided by Archimedes. 'Give me