Suppose a car can accelerate at 1m/s2. How large a break in traffic is needed to enter a highway where cars?

April 27th, 2009 | by Michael |
cars
Vivian C asked:


Suppose that a car can accelerate to 1m/s2. How great a break in traffic? required to enter into a main road where cars are moving a 20m / s if the drive wants to avoid forcing the diaries following car to slow down or come close to pi? close to 25m?

JAMAR

  1. 2 Responses to “Suppose a car can accelerate at 1m/s2. How large a break in traffic is needed to enter a highway where cars?”

  2. By Madhukar Daftary on Apr 29, 2009 | Reply

    This question cannot be answered. It will be wrong to assume that car can decelerate at the same rate at which it can accelerate. If it is given that the car can decelerate at the rate of 1 m/s^2, then the question can be answered as under.

    If s = distance covered after applying brakes,
    v^2 = u^2 - 2as
    => s = u^2 / 2a = (20)^2 / 2 * 1 = 200 m
    If a minimum of 25 m is to be kept, The break in traffic needed = 225 m

  3. By Catenary on May 2, 2009 | Reply

    Assumptions:

    1) The entering car is stopped
    2) The entering car begins accelerating as soon as the rear bumper of the car it will fall in behind passes its front bumper.

    What distance does it take a car to accelerate from 0 to 20 m/s at a rate of 1m/s²?

    1) Final velocity = initial velocity + acceleration * time
    2) Distance = initial velocity * time + 1/2 acceleration * time²

    Plugging in the known values, the first equation becomes

    20 m/s = 0 m/s + 1m/sec² * x

    x = 20 sec

    Now we can calcuate the second equation

    D = 0 m/s * 20 sec + 1/2 * 1 m/s² * (20 sec)²

    D = 0 m + 200 m

    If we need to keep a 25 m space behind us, that gets added to the necessary distance.

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