( Then ( ( the impulse ) ( ( is ( being ( applied ( for ( ( a ( longer period ) ) ( of time ) ) ) ) ) ) . ) ) )
(ROOT (S (RB Then) (NP (DT the) (NN impulse)) (VP (VBZ is) (VP (VBG being) (VP (VBN applied) (PP (IN for) (NP (NP (DT a) (JJR longer) (NN period)) (PP (IN of) (NP (NN time)))))))) (. .)))
Then the impulse is being applied for a longer period of time.
(ROOT (S (NP (NNP Impulse)) (VP (VBZ is) (NP (NP (DT the) (NN quantity)) (PP (IN of) (NP (NP (NN force)) (VP (VBN multiplied) (PP (IN by) (NP (NP (DT the) (NN time)) (SBAR (S (NP (PRP it)) (VP (VBZ is) (VP (VBN applied)))))))))))) (. .)))