A rocket traveling at 0.50c sets out for the nearest star, Alpha Centauri, which is 4.3 ly away from earth. It will return to earth immediately after reaching Alpha Centauri. What distance will the rocket travel and how long will the journey last according to (a) stay-at-home earthlings and (b) the rocket crew? (c) Which answers are the correct ones, those in part a or those in part b?

Chapter5:Newtonâ€™sLaws Thegoalofmechanicsistotakewhatisknownaboutasystemofobjects andtotherebydeterminewhataccelerationofeachofthoseobjectwillbe. Principleofinertiaâ€“abodymovingonalevelsurfacewillcontinueinth e samedirectionatconstantspeedunlessdisturbed LawI:Everybodypreservesinitsstateofrest,orofuniformmotionina straightline,unlessitiscompelledtochangethatstatebyforcesimpressed...