How Long to Overtake at Different Speeds?

AI Thread Summary
To determine how long it takes for a car traveling at 60 km/h to overtake another car at 40 km/h, the relative speed is calculated as 20 km/h. Given that the initial distance between the cars is 100 meters, the time to overtake can be found using the formula time = distance/speed. Converting the speed to meters per second, the calculation reveals that it takes 15 seconds to complete the overtaking maneuver. Understanding relative velocity is crucial for solving such problems effectively.
meredith
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Homework Statement


how long does it take a car traveling in the left lane at 60 km/h to overtake another car traveling in the right lane at 40 kn/h when the cars front bumpers are initially 100 m apart?


Homework Equations


relative velocity equations
V ab = v ae + V be


The Attempt at a Solution


i don't really know my work doesn't make sense and there's no sense typing it all in here cause its wrong and i can't even get al the symbols
 
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Relative to the 40km/h car, the car in the left lane is traveling 20km/h.

So now you have relative velocity, they give you relative distance (100m) solve for time.

Hint:
velocity = distance / time

Hint #2:
Don't forget to convert relative velocity to m/s if you want it in si units.
 

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