An uncontrolled 1050 kg car strikes squarely a motorway crash cushion in which the car is brought to rest by successively crushing steel barrels. The length of the crash cushion is 6.1 m, and the magnitude F of the force required to crush the barrels as a function of the distance x the car has moved into the cushion is given by (0 < x < 1.7m) (1.7 < x < 4.7m) 80KN 110kN 155kN (4.7 < x < 6.1m) a) Determine an expression for the work done by the force F as a function of x. b) If the car strikes the crash cushion with a velocity of 119 km/h, determine the distance the car will move into the cushion before it comes to rest and the maximum deceleration of the car. c) Determine the maximum velocity with which the car can strike the cushion so that it will not hit the wall behind the cushion.

An uncontrolled 1050 kg car strikes squarely a motorway crash cushion in which the car is brought to rest by successively crushing steel barrels. The length of the crash cushion is 6.1 m, and the magnitude F of the force required to crush the barrels as a function of the distance x the car has moved into the cushion is given by (0 < x < 1.7m) (1.7 < x < 4.7m) 80KN 110kN 155kN (4.7 < x < 6.1m) a) Determine an expression for the work done by the force F as a function of x. b) If the car strikes the crash cushion with a velocity of 119 km/h, determine the distance the car will move into the cushion before it comes to rest and the maximum deceleration of the car. c) Determine the maximum velocity with which the car can strike the cushion so that it will not hit the wall behind the cushion.

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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