Compound lever the force of pushing back the stick to the levers and they rub against the wheels, using friction to slow and eventually stop the train. These are everyday applications of this mechanism. A piano key is a compound lever of the first-class, since the fulcrum is between the weight to be moved and the power. The purpose of this lever is to translate a small movement (depression of the key) into a larger and fast movement of the hammer on the strings. The quality of the resulting tone depends on whether the final speed is brought about by gradual or
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