( ( ( The momentum ) ( of ( an object ) ) ) ( ( is ( changed ( by ( ( giving it ) ( an impulse ) ) ) ) ) . ) )
(ROOT (S (NP (NP (DT The) (NN momentum)) (PP (IN of) (NP (DT an) (NN object)))) (VP (VBZ is) (VP (VBN changed) (PP (IN by) (S (VP (VBG giving) (NP (PRP it)) (NP (DT an) (NN impulse))))))) (. .)))
The momentum of an object is changed by giving it an impulse .
(ROOT (S (NP (NP (NNP Change)) (PP (IN in) (NP (NP (NN momentum)) (PP (IN in) (NP (DT an) (NN object)))))) (VP (VBZ is) (ADJP (JJ equivalent) (PP (TO to) (NP (NN impulse))))) (. .)))