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 Brothers Lever Brothers Lever Brothers was a British manufacturing company founded in 1885 by brothers William Hesketh Lever (1851–1925) and James Darcy Lever (1854–1916). They invested in and successfully promoted a new soap-making process invented by chemist William Hough Watson. In 1930, Lever Brothers merged with Margarine Unie to form Unilever. Starting with a small grocery business begun by his father, William Lever and his brother James entered the soap business in 1885 by buying a small soap works in Warrington. The brothers teamed up with a Bolton chemist, William Hough Watson, who became an early business partner. Watson invented the