Engineering Mechanics - DynamicsChapter 12dd2vt3t2−()+12at3t2−2−=0vat3t2−−=t1t2t3d1d2⎛⎜⎜⎜⎜⎜⎜⎝⎞⎟⎟⎟⎟⎟⎟⎠Findt1t2,t3,d1,d2,=t1t2t3⎛⎜⎜⎝⎞⎟⎟⎠122032⎛⎜⎜⎝⎞⎟⎟⎠s=d1d2⎛⎜⎝⎞⎟⎠360840⎛⎝⎞⎠m=t332 s=Problem 12-31Determine the time required for a car to travel a distance dalong a road if the car starts fromrest, reaches a maximum speed at some intermediate point, and then stops at the end of theroad. The car can accelerate at a1and decelerate at a2. Given:d1km=a11.5ms2=a22ms2=Let t1be the time at which it stops accelerating and tthe total time.Solution:Guessest11s=d11m=t3s=v11ms=Givend1a12t12=v1a1t1=v1a2tt1−=1v11−+1
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