Ask Question
2 May, 06:20

The brakes on your automobile are capable of creating a deceleration of 4.7 m/s². If you are going 140 km/h and suddenly see a state trooper, what is the minimum time in which you can get your car under the 81 km/h speed limit?

+1
Answers (1)
  1. 2 May, 06:29
    0
    2.4seconds

    Explanation:

    A body decelerating is known to have a negative acceleration.

    Acceleration is the change in velocity of a body with respect to time. Mathematically,

    Acceleration = change in velocity/time

    Change in velocity = final velocity - initial velocity

    Acceleration = final velocity (v) - initial velocity (u) / time taken (t)

    This same formula will be used as the deceleration formula i. e

    Deceleration = v-u/t

    Given deceleration = - 4.7m/s² (negative acceleration)

    v = 81km/hr = (81000/3600) m/s = 22.5m/s

    u = 140km/hr = (140,000/3600) m/s = 38.8m/s

    Substituting the values into the deceleration formula we have;

    -4.7 = 22.5-38.8/t

    -4.7 = - 11.3/t

    -4.7t = - 11.3

    t = - 11.3/-4.7

    t = 2.4seconds

    The minimum time in which you can get your car under the 81 km/h speed limit is 2.4seconds
Know the Answer?
Not Sure About the Answer?
Find an answer to your question 👍 “The brakes on your automobile are capable of creating a deceleration of 4.7 m/s². If you are going 140 km/h and suddenly see a state ...” in 📗 Physics if the answers seem to be not correct or there’s no answer. Try a smart search to find answers to similar questions.
Search for Other Answers