Objects A and B are at the origin. If object A moves to #(9 ,-7 )# and object B moves to #(-8 ,6 )# 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.

Question

Objects A and B are at the origin.  If object A moves to #(9  ,-7  )# and object B moves to #(-8  ,6  )# 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.

Nora Arzate · Accepted Answer

#v_"AB"=7,1" "m/s#
#alpha=143 ^o " from east"#

#Delta s=21,4 " "m#
#v_"AB"=(Delta s)/(Delta t)#
#v_"AB"=(21,4)/3#
#v_"AB"=7,1" "m/s#
#tan (180-alpha)=13/17=37 ^o#
#alpha=180-37#
#alpha=143 ^o " from east"#

Julia Aguilar · Answer

undefined To find the relative velocity of object B from the perspective of object A, we need to subtract the velocity of object A from the velocity of object B.

Velocity of object A = (9 m/s, -7 m/s)
Velocity of object B = (-8 m/s, 6 m/s)

Relative velocity of B from A = Velocity of B - Velocity of A
= (-8 m/s, 6 m/s) - (9 m/s, -7 m/s)
= (-8 - 9 m/s, 6 - (-7) m/s)
= (-17 m/s, 13 m/s)

Therefore, the relative velocity of object B from the perspective of object A is (-17 m/s, 13 m/s).