Objects A and B are at the origin. If object A moves to #(-4 ,-9 )# and object B moves to #(1 ,-1 )# over #8 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
Nov 18, 2017

The relative veocity is #= <17/8, 1> ms^-1#

Explanation:

enter image source here

The absolute velocity of #A# is #v_A= 1/8<-4,-9> = <-2, -9/8> ms^-1#

The absolute velocity of #B# is #v_B= 1/8<1,-1> = <1/8, -1/8> ms^-1#

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

#v_(B//A)=v_B-v_A = <1/8, -1/8> - <-2, -9/8>#

#= <1/8+2, -1/8+9/8 >#

#= <17/8, 1> ms^-1#