Section 3-8: Relative Velocity. Section 3-8: Relative Velocity. A useful example of vector addition ! Example: 2 trains approaching each other (along a line) at 95 km/h each, with respect to the Earth.
Velocity depends on reference frame!!
Proper subscript labeling of velocities
Second = reference frame, R.
vFB = velocity of the Fisherman with respect to the Boat:
vFS = vFB + vBW + vWS
vAB = -vBA
vPA = 200 km/h , N
vAG = 100 km/h , from NE
vPG = vPA + vAG
Use the rules of analytic addition:
Compute components of vPA & vAG
Add these to get components of vPG.
Compute the length & angle of vPG