Physics Lab Question-- any ideas? For our physics lab hung a mass attached to spring above a motion detector. First we took some data with the spring at rest. Using this data, we determined our zo value. Then we set the spring in motion and took data. Using position, velocity, and time data, we calculated K, U, & K+U = mechanical energy (E) We were given this info to plot the data on a graph x= -.5(z-zo)^2 y=.5Mv^2 y=kx+E Plotting this on a graph, we determined the value of k & E U= .5(z-zo)^2 K= .5mv^2 Now the question: Could this lab be done by hanging the spring mass system from a force probe instead of a distance probe ? How would you do the analysis? I think this could be done, but I am having trouble visualizing how. Every idea I come up with needs the distance probe also. For example, I thought about how Force= -dU/ds and had this idea: Pull down on the mass-spring system to a measured distance and record the reading of the force probe there. From this you can determine the potential energy and thus the mechanical energy, since there is no KE initially. Then to determine k, hang the mass spring system from a force probe & record the force reading. Then measure the distance the spring stretches from its eq. position using F=-kx you can determine k. But all of these ideas seem to require distance. I have thought long and hard about this but I just can seem to find the right idea.