Motion of Two Cars: Velocity Calculation in Same Direction - 1 km/h

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The discussion centers on calculating the relative velocity of two cars, a Ford traveling at 59 km/h and a Holden at 60 km/h, both moving in the same direction. The incorrect initial calculation of 119 km/h arises from adding their speeds instead of finding the difference. The correct method involves subtracting the Ford's speed from the Holden's speed, resulting in a relative velocity of 1 km/h. This approach emphasizes understanding the perspective of one car observing the other. Proper vector handling is crucial for accurately determining relative motion in such scenarios.
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Homework Statement



A ford is traveling at 59 km/h while a Holden has a speed of 60 km/h

Calculate the velocity of the Holden relative to the Ford when they are traveling in:

in the same direction

The Attempt at a Solution



59+60 = 119 km/h

However the answer is 1 km/h.

I don't understand why it's 60-59 km/h
 
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Have you drawn out this problem? It's pretty easy to figure out.
 
there are two vectors 59 km/h and 60km/h
and they're traveling in the same direction.
Shouldn't you add the two vectors?
 
missmerisha said:
Calculate the velocity of the Holden relative to the Ford when they are traveling in:

If you want to know the velocity of the two cars relative to one another, what is the proper way to handle the vectors. Put it this way. If you were driving one car and looking at the the other car, what would you see the other car doing?
 

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