Objects A and B are at the origin. If object A moves to (3,6) and object B moves to (6,5) over 1s, 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 30, 2017

vBw.r.tA=3ˆi11ˆj

Explanation:

ri= initial displacement vector
rj=final displacement vector
rA=Displacement vector of A
rB=Displacement vector of B
w.r.t=with respect to

ri=0
rf=3ˆi+6ˆj
rA=rfri
rA=3ˆi+6ˆj

ri=0
rf=6ˆi5ˆj
rB=rfri
rB=6ˆi5ˆj

rBw.r.tA=rBrA

rBw.r.tA=3ˆi11ˆj(m)

vBw.r.tA=rBw.r.tAt

vBw.r.tA=3ˆi11ˆj(m)1s

vBw.r.tA=3ˆi11ˆj(ms1)

vBw.r.tA=130ms1