# Relative velocity in Two Dimension

## Relative velocity in Two Dimension

we have already seen the Relative Velocity in 1D motion.Lets see how to define it in two -dimensional motion For two objects A and B moving with the uniform velocities VA and VB.
Relative velocity is defined as
VBA=VB-VA
where VBA is relative velocity of B relative to A

Similarly relative velocity of A relative to B
VAB=VA-VB
we will need to add or subtracting components along x & y direction to get the relative velocity
Suppose
vA=vxai + vyaj
vB=vxbi + vybj

Relative velocity of B relative to A
=vxbi + vybj -(vxai + vyaj)
=i(vxb-vxa) + j(vyb-vya)

For three dimensions motion
vA=vxai + vyaj +vzaz
vB=vxbi + vybj + vzbz

Relative velocity of B relative to A
=vxbi + vybj + vzbz -(vxai + vyaj +vzaz)
=i(vxb-vxa) + j(vyb-vya)+z(vyb-vya)