A student carries out an investigation on a spring. The graph shows how the length of the spring changes with the force acting on the spring. What is the spring constant of the spring?
- A$0.17\,\text{N m}^{-1}$
- B$0.25\,\text{N m}^{-1}$
- C$4.0\,\text{N m}^{-1}$
- D$6.0\,\text{N m}^{-1}$