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A curve on a road has a radius of curvature of 97.6 m. If the grip of the tires with the pavement allows a maximum centripetal acceleration of 0.5 g, what is the maximum speed in km/h at which the curve can be taken?

Answer :

To find the maximum speed at which a car can navigate a curve without skidding, we need to use the concept of centripetal acceleration. Here are the steps to solve this:

  1. Understanding Centripetal Acceleration:
    Centripetal acceleration (
    a_c) is given by the formula:

    [tex]a_c = \frac{v^2}{r}[/tex]

    where:

    • [tex]v[/tex] is the speed of the vehicle,
    • [tex]r[/tex] is the radius of curvature of the curve.
  2. Maximum Centripetal Acceleration:
    The maximum centripetal acceleration can be determined by the grip of the tires with the pavement. In this case, the maximum centripetal acceleration is given as 0.5 g, where g is the acceleration due to gravity (approximately 9.81 m/s²).

    Therefore,

    [tex]a_{max} = 0.5 \cdot g = 0.5 \cdot 9.81 \approx 4.905 \text{ m/s}^2[/tex]

  3. Setting Up the Equation:
    Now we can set this equal to the centripetal acceleration formula:

    [tex]\frac{v^2}{r} = a_{max}[/tex]

    Substituting the value of [tex]a_{max}[/tex] and the given radius (97.6 m) into the equation, we have:

    [tex]\frac{v^2}{97.6} = 4.905[/tex]

  4. Solving for Speed:
    Rearranging the equation to solve for speed (v):

    [tex]v^2 = 4.905 \cdot 97.6[/tex]

    [tex]v^2 \approx 479.388[/tex]

    Taking the square root:

    [tex]v \approx \sqrt{479.388} \approx 21.9 \text{ m/s}[/tex]

  5. Converting from m/s to km/h:
    To convert the speed from meters per second to kilometers per hour, use the conversion factor (1 m/s = 3.6 km/h):

    [tex]v \approx 21.9 \text{ m/s} \cdot 3.6 = 78.84 \text{ km/h}[/tex]

Final Answer:
The maximum speed at which the curve can be taken without skidding is approximately 78.84 km/h.

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