Sally asked in Science & MathematicsPhysics · 5 months ago

to avoid getting caught speeding, what is the maximum speed at which you should complete your ?

trip if you realize 10 km into your 20 km route that you have been traveling at 125 km/h when the speed limit is 100 km/h? (Hint: the answer is not 75 km/h.) Illustrate your solution with a graph

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  • 5 months ago

    This is a pretty dumb question.  If you have not been caught during your 10 km drive at 125 km/h, then you will be safe if you do the remaining 10 km at 100 km/h.  Where is the  problem, exactly ?

  • 5 months ago

    So I'm assuming what you're asking here is what speed you can go for the rest of the trip without having your average speed exceed 100 km/h.

    Keep in mind average speed is defined as total distance / time, so we can use this to find the minimum total time for the trip.

    100 km/h >= 20 km / t --> t >= 0.2 hours

    Next, we need to know how much time we've already used, which we can get from the average speed and distance from the first leg.

    125 km/h = 10 km/t_used --> t_used = 0.08 hours

    If we need to take at least 0.2 hours and we've used 0.08, then we need to take 0.12 hours for the last 10 kilometers of the trip.

    Speed for the next 10 km = 10 km / 0.12 hours = 83.33 km/h

    Hope this helps!

  • Anonymous
    5 months ago

    If you where caught, you where not going fast enough.

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