Engineering Board Exam Reviewer · Applications: Centroid, Work, and Moment of Inertia · easy

A variable force F(x)=6x2+4x newtons acts along the x-axis. How much work, in joules, is done in moving an object from x=1 m to x=4 m?

  1. 160
  2. 156
  3. 84
  4. 312

Answer

B. 156

Solution

W= 14≤ft(6x2+4x )dx=≤ft[2x3+2x2 ]14=(128+32)-(2+2)=156 J.

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