( ( The ( second one ) ) ( ( ( will never ) ( ( come back ) ( ( because , ) ( ( when ( ( its speed ) decreases ) ) ( , ( ( ( the distance ) ( between ( the ( two magnets ) ) ) ) ( increases ( by ( ( ( as much ) , ) ( exactly ( compensating ( ( the loss ) ( of speed ) ) ) ) ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (DT The) (JJ second) (NN one)) (VP (MD will) (ADVP (RB never)) (VP (VB come) (PRT (RP back)) (SBAR (IN because) (, ,) (S (SBAR (WHADVP (WRB when)) (S (NP (PRP$ its) (NN speed)) (VP (VBZ decreases)))) (, ,) (NP (NP (DT the) (NN distance)) (PP (IN between) (NP (DT the) (CD two) (NNS magnets)))) (VP (VBZ increases) (PP (IN by) (NP (NP (QP (RB as) (JJ much))) (, ,) (VP (ADVP (RB exactly)) (VBG compensating) (NP (NP (DT the) (NN loss)) (PP (IN of) (NP (NN speed)))))))))))) (. .)))
The second one will never come back because, when its speed decreases, the distance between the two magnets increases by as much, exactly compensating the loss of speed.
(ROOT (S (S (VP (VBG Increasing) (NP (NP (DT the) (NN distance)) (PP (IN between) (NP (DT the) (CD two) (NNS magnets)))))) (VP (MD will) (VP (VB cause) (NP (DT a) (NN decrease)) (PP (IN in) (NP (NP (DT the) (NN force)) (PP (IN of) (NP (NP (NN attraction)) (PP (IN between) (NP (CD two) (NNS magnets))))))))) (. .)))
Increasing the distance between the two magnets will cause a decrease in the force of attraction between two magnets.