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Contact forces

AP.PHYS: INT‑3.C (EU), INT‑3.C.4 (EK), INT‑3.C.4.1 (LO), INT‑3.C.4.2 (LO)
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The spring in a pinball machine has a spring constant k of 2, comma, 130, start fraction, start text, N, end text, divided by, start text, m, end text, end fraction.
What is the magnitude of the force required to compress this spring 4, point, 5, start text, c, m, end text?
Write your answer using two significant figures.
  • Your answer should be
  • an integer, like 6
  • a simplified proper fraction, like 3, slash, 5
  • a simplified improper fraction, like 7, slash, 4
  • a mixed number, like 1, space, 3, slash, 4
  • an exact decimal, like 0, point, 75
  • a multiple of pi, like 12, space, start text, p, i, end text or 2, slash, 3, space, start text, p, i, end text
start text, N, end text