Ask Question
26 September, 22:56

If the coefficient of kinetic friction between tires and dry pavement is 0.84, what is the shortest distance in which you can stop an automobile by locking the brakes when traveling at 29.0 m/s

+4
Answers (1)
  1. 27 September, 00:16
    0
    The shortest distance in which you can stop the automobile by locking the brakes is 53.64 m

    Explanation:

    Given;

    coefficient of kinetic friction, μ = 0.84

    speed of the automobile, u = 29.0 m/s

    To determine the the shortest distance in which you can stop an automobile by locking the brakes, we apply the following equation;

    v² = u² + 2ax

    where;

    v is the final velocity

    u is the initial velocity

    a is the acceleration

    x is the shortest distance

    First we determine a;

    From Newton's second law of motion

    ∑F = ma

    F is the kinetic friction that opposes the motion of the car

    -Fk = ma

    but, - Fk = - μN

    -μN = ma

    -μmg = ma

    -μg = a

    - 0.8 x 9.8 = a

    -7.84 m/s² = a

    Now, substitute in the value of a in the equation above

    v² = u² + 2ax

    when the automobile stops, the final velocity, v = 0

    0 = 29² + 2 (-7.84) x

    0 = 841 - 15.68x

    15.68x = 841

    x = 841 / 15.68

    x = 53.64 m

    Thus, the shortest distance in which you can stop the automobile by locking the brakes is 53.64 m
Know the Answer?
Not Sure About the Answer?
Find an answer to your question ✅ “If the coefficient of kinetic friction between tires and dry pavement is 0.84, what is the shortest distance in which you can stop an ...” in 📘 Physics if you're in doubt about the correctness of the answers or there's no answer, then try to use the smart search and find answers to the similar questions.
Search for Other Answers