The document summarizes an experiment to determine the spring constant of simple extension springs and springs connected in parallel using Hooke's law. Key points: 1) Springs were loaded with weights in increments and the extension was measured to calculate spring constant from the slope of force vs. extension graphs. 2) Theoretical spring constants were also calculated using the springs' material properties and dimensions. 3) For springs in parallel, the total spring constant was calculated as the sum of the individual spring constants, matching the experimental results.