Which angle should I use for the relative velocity of bus to car ?

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Which angle (1) or (2) should I use for the direction of Vb-c?
If I use (1), is the answer become SϴE and if I use (2), the answer become NϴW?
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1 Answer
May 27, 2018

I vote for angle 2.

Explanation:

I am not 100% sure that I am interpreting "the bus to the car" correctly. This is how I interpret scenario (i): it is asking for the velocity of the bus as observed from the car.

The driver of the car would have to look back over his/her left shoulder to see the bus. The bus is getting farther away with each passing second.

Another way to think about it: after 10 s, the bus is some distance to the north-west of the car. After another 10 s, the bus is an even greater distance to the north-west. So it is going away from the driver, to the north-west. Therefore, I vote for angle 2.

I hope this helps,
Steve