Question
At an accident scene on a level road, investigators measure a car’s skid mark to be 35 m long. The coefficient of kinetic friction between the tire and the road was 0.65. (a) Find an expression for the friction acting on the car. (b) Find an expression for the change in kinetic energy of the car from just before braking to a complete stop. (c) Use the Work- Energy Theorem to determine the speed of the car just before braking. (The car’s mass does not matter.)
show your work, including diagrams, algebraic equations, and enough written explanations that somebody who is not familiar with the problem could understand what you are doing.
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