6. Suppose that, while driving on a dry road, a driver slams on the brakes. Let D be the distance (in feet) that the car will skid and S be the speed (in mph) before braking. The relationship between D and S is described by the model S = √√30 F. D, where F is a drag factor, which is a measure of the roughness of the surface of the road. The drag factor on new concrete is 0.95, and the drag factor on polished concrete or asphalt is 0.75. A motorist who was involved in an accident claims that he was driving at the posted speed limit of 60 mph. A police officer measures the car's skid marks on the asphalt road to be 210 feet long. Assuming that the motorist applied the brakes suddenly, estimate the speed at which the motorist was traveling before braking. (Round to the nearest tenth of a mph.)

6. Suppose that, while driving on a dry road, a driver slams on the brakes. Let D be the distance (in feet) that the car will skid and S be the speed (in mph) before braking. The relationship between D and S is described by the model S = √√30 F. D, where F is a drag factor, which is a measure of the roughness of the surface of the road. The drag factor on new concrete is 0.95, and the drag factor on polished concrete or asphalt is 0.75. A motorist who was involved in an accident claims that he was driving at the posted speed limit of 60 mph. A police officer measures the car's skid marks on the asphalt road to be 210 feet long. Assuming that the motorist applied the brakes suddenly, estimate the speed at which the motorist was traveling before braking. (Round to the nearest tenth of a mph.)

University Physics Volume 1

18th Edition

ISBN:9781938168277

Author:William Moebs, Samuel J. Ling, Jeff Sanny

Publisher:William Moebs, Samuel J. Ling, Jeff Sanny

Chapter5: Newton's Law Of Motion

Section: Chapter Questions

Problem 89AP: In building a house, carpenters use nails from a large box. The box is suspended from a spring twice...

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