( ( Since ( ( ( the forces ) ( between ( the ( two objects ) ) ) ) ( ( are ( equal ( in ( ( magnitude and ) opposite ) ) ) ) ( ( ( ( in direction ) , ) and ) ( since ( ( the times ) ( ( for which ) ( ( these ( forces act ) ) ( are ( equal ( in magnitude ) ) ) ) ) ) ) ) ) ) ) ( , ( it ( ( follows ( that ( ( ( the impulses ) ( experienced ( by ( the ( two objects ) ) ) ) ) ( ( ( are also ) ( equal ( in ( ( magnitude and ) opposite ) ) ) ) ( in direction ) ) ) ) ) . ) ) ) )
(ROOT (S (SBAR (IN Since) (S (NP (NP (DT the) (NNS forces)) (PP (IN between) (NP (DT the) (CD two) (NNS objects)))) (VP (VBP are) (ADJP (JJ equal) (PP (IN in) (NP (NN magnitude) (CC and) (NN opposite)))) (PP (PP (IN in) (NP (NN direction))) (, ,) (CC and) (PP (IN since) (NP (NP (DT the) (NNS times)) (SBAR (WHPP (IN for) (WHNP (WDT which))) (S (NP (DT these) (NNS forces) (NN act)) (VP (VBP are) (ADJP (JJ equal) (PP (IN in) (NP (NN magnitude))))))))))))) (, ,) (NP (PRP it)) (VP (VBZ follows) (SBAR (IN that) (S (NP (NP (DT the) (NNS impulses)) (VP (VBN experienced) (PP (IN by) (NP (DT the) (CD two) (NNS objects))))) (VP (VBP are) (ADVP (RB also)) (ADJP (JJ equal) (PP (IN in) (NP (NN magnitude) (CC and) (NN opposite)))) (PP (IN in) (NP (NN direction))))))) (. .)))
Since the forces between the two objects are equal in magnitude and opposite in direction, and since the times for which these forces act are equal in magnitude, it follows that the impulses experienced by the two objects are also equal in magnitude and opposite in direction.
(ROOT (S (NP (NP (NNS Objects)) (PP (IN on) (NP (NN earth)))) (VP (VBP have) (NP (NP (CD two) (NNS forces)) (VP (VBG acting) (PP (IN on) (NP (PRP them))) (PP (IN at) (NP (DT all) (NNS times)))))) (. .)))