Relative velocity of 2 vehicles

AI Thread Summary
Two vehicles depart from a fork, with Vehicle A traveling at 85 km/h north-east and Vehicle B at 104 km/h directly east. The discussion centers on calculating the relative velocity of Vehicle A with respect to Vehicle B using the equation aVb = Va - Vb. There is confusion regarding the direction of Vehicle B, with some participants mistakenly interpreting its direction as west. Clarifications highlight that the equation accounts for relative motion, emphasizing that if a slower vehicle is overtaken, it appears to move backward relative to the faster one. Understanding the correct application of relative velocity is crucial for accurate calculations.
Aashish Bharat
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Two vehicles leave simultaneously from a fork in a road. Vehicle A travels at a velocity of 85 km/h north-east. Vehicle B travels at 104 km/h directly east. Calculate the velocity of vehicle A relative to the velocity of vehicle B.

Answer (from memorandum): http://imgur.com/a/L0prH

I do not understand why is Vehicle B traveling west, an explanation on how why this was done would be appreciated!

aVb = Va - Vb (Velocity of A relative to velocity of B) when do you use this equation?
 
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If you are in a car and get overtaken by another car, then relative to the faster car you are going backwards. Not so?
 
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PeroK said:
If you are in a car and get overtaken by another car, then relative to the faster car you are going backwards. Not so?
Damn it, they took the opposite direction of Vb from the equation aVb = Va - Vb. I should have known better
 

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