( ( ( The amount ) ( of ( lift force ) ) ) ( ( ( depends ( ( ( ( ( on ( ( the ( pressure difference ) ) ( between ( ( ( the top ) and ) ( the bottom ) ) ) ) ) , ) and ) also ) ( on ( ( the amount ) ( of ( surface area ) ) ) ) ) ) ( that ( ( the pressure ) ( acts on ) ) ) ) . ) )
(ROOT (S (NP (NP (DT The) (NN amount)) (PP (IN of) (NP (NN lift) (NN force)))) (VP (VBZ depends) (PP (PP (IN on) (NP (NP (DT the) (NN pressure) (NN difference)) (PP (IN between) (NP (NP (DT the) (NN top)) (CC and) (NP (DT the) (NN bottom)))))) (, ,) (CC and) (ADVP (RB also)) (PP (IN on) (NP (NP (DT the) (NN amount)) (PP (IN of) (NP (NN surface) (NN area)))))) (SBAR (IN that) (S (NP (DT the) (NN pressure)) (VP (VBZ acts) (PRT (RP on)))))) (. .)))
The amount of lift force depends on the pressure difference between the top and the bottom, and also on the amount of surface area that the pressure acts on.
(ROOT (S (NP (NN Pressure)) (VP (VBZ is) (VP (VBN defined) (PP (IN in) (NP (NN physics))) (PP (IN as) (NP (NP (DT the) (NN amount)) (PP (IN of) (NP (NP (NN force)) (VP (VBG pushing) (PP (IN against) (NP (DT a) (VBN given) (NN area)))))))))) (. .)))