( ( Centripetal force ) ( -LRB- ( ( Mech . ) -RRB- ) ) )
(ROOT (NP (NP (JJ Centripetal) (NN force)) (PRN (-LRB- -LRB-) (NP (NNP Mech) (. .)) (-RRB- -RRB-))))
Centripetal force (Mech.)
(ROOT (S (NP (JJ Centripetal) (NN force)) (VP (VBZ is) (NP (NP (DT the) (NN force)) (SBAR (WHNP (WDT that)) (S (VP (VBZ causes) (NP (JJ centripetal) (NN acceleration))))))) (. .)))