Objects A and B are at the origin. If object A moves to #(-7 ,4 )# and object B moves to #(-3 ,2 )# over #3 s#, what is the relative velocity of object B from the perspective of object A? Assume that all units are denominated in meters.

1 Answer
Jul 20, 2017

The relative velocity is #=2/3<2, -1> ms^-1#

Explanation:

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The absolute velocity of #A# is #v_A=1/3<-7,4> = <-7/3,4/3>#

The absolute velocity of #B# is #v_B=1/3<-3,2> = <-1,2/3>#

The relative velocity of #B# with respect to #A# is

#v_(B//A)=v_B-v_A#

#=<-1,2/3> - <-7/3,4/3>#

#=<-1+7/3, 2/3-4/3>#

#=<4/3, -2/3> ms^-1#