Lab 7: Mass-Spring Systems Table: Spring Constant of Spring 1 Mass (g) Change in Length (cm) Spring Constant (N/m) 50g 8 100g 16 250g 40 Kavg=

To find the spring constant using Hooke’s Law, we will need to rearrange equation 1 and solve for k.

                                 k = F
                                       x
Note that at equilibrium, the weight of the mass, mg, is equal to the spring force. Therefore,
k = mg/ x               [3] Rearranged Hooke’s Law equation

This means you can use the k = mg/x to find the spring constant. In this formula, g=9.8 m/s2 is the acceleration due to gravity. Before you substitute your values into the spring constant equation, you will need to convert the mass from grams into kilograms and the change in length from centimeters into meters. If you do not convert the units, then your spring constant will not have the units N/m, and it will be incorrect. Repeat the above procedure with 100g and 250g. Because the spring has not changed, all three values for the spring constant should be similar to each other. If they are very different, you should reread the directions and try again. Finally, calculate the average spring constant and enter it into the last row of Data Table 1.