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

A spring requires a force of 20 N to stretch it 0.1 m beyond its natural length. Using Hooke's Law, find the work done in stretching it 0.2 m beyond natural length.

  1. 4 J
  2. 2 J
  3. 8 J
  4. 40 J

Answer

A. 4 J

Solution

k=F/x=20/0.1=200 N/m. W= 00.2200x,dx=100(0.2)2=4 J.

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