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Question
(a) Calculate the force needed to bring a 950-kg car to rest from a speed of 90.0 km/h in a distance of 120 m (a fairly typical distance for a non-panic stop). (b) Suppose instead the car hits a concrete abutment at full speed and is brought to a stop in 2.00 m. Calculate the force exerted on the car and compare it with the force found in part (a).
Question by OpenStax is licensed under CC BY 4.0.
Final Answer
  1. $-2.47 \times 10^{3} \textrm{ N}$
  2. $-1.48 \times 10^{5}\textrm{ N}$. The force when hitting the concrete abutment is greater by a factor of $60.0$
Solution Video

OpenStax College Physics Solution, Chapter 7, Problem 12 (Problems & Exercises) (3:22)

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