The mass center of the rear-engine 3120-lb car is at G. Determine the normal forces NA and Ng exerted by the road on the front and rear pairs of tires for the conditions of (a) being stationary and (b) braking from a forward velocity v with all wheels locked. The coefficient of kinetic friction is 0.95 at all tire/road interfaces. Express all answers in terms of pounds and as percentages of the vehicle weight. Answers: (a) While stationary: NA = Ne= NA = 72"-50" i (b) While braking: Ng= B 21" lb = i lb = i lb = lb = % of the total weight % of the total weight % of the total weight

The mass center of the rear-engine 3120-lb car is at G. Determine the normal forces NA and Ng exerted by the road on the front and rear pairs of tires for the conditions of (a) being stationary and (b) braking from a forward velocity v with all wheels locked. The coefficient of kinetic friction is 0.95 at all tire/road interfaces. Express all answers in terms of pounds and as percentages of the vehicle weight. Answers: (a) While stationary: NA = Ne= NA = 72"-50" i (b) While braking: Ng= B 21" lb = i lb = i lb = lb = % of the total weight % of the total weight % of the total weight

International Edition---engineering Mechanics: Statics, 4th Edition

4th Edition

ISBN:9781305501607

Author:Andrew Pytel And Jaan Kiusalaas

Publisher:Andrew Pytel And Jaan Kiusalaas

Chapter7: Dry Friction

Section: Chapter Questions

Problem 7.49P

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