If a spring is not compressed or stretched too much, it should obey Hooke’s Law. According to this Law, if an additional force, Fy, acts on the spring then the change in the spring length, y, will be directly proportional to that force. The spring constant, k, for a Hooke’s Law spring is defined as the constant of proportionality that relates the two variables, so that Fy = ky. We have created a digital movie that shows a spring clamped to a rod so its top end cannot move. The movie actually consists of a series of still “photos” showing the spring stretching as more and more mass is added to its bottom end.


In this activity, you will

  • Verify Hooke’s Law for a spring and determine its spring constant, k.