Objects A and B are at the origin. If object A moves to #(5 ,-7 )# and object B moves to #(7 ,4 )# over #2 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
Aug 28, 2017

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

Explanation:

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The absolute velocity of #A# is #v_A=1/2<5,-7> = <5/2, -7/2>#

The absolute velocity of #B# is #v_B=1/2<7,4> = <7/2, 2>#

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

#v_(B//A)=v_B-v_A=<7/2, 2> - <5/2, -7/2>#

#= <7/2-5/2, 2-7/2>#

#= <1, -3/2 >#