If mass is subject only to a force of the form given by F=-kx it will move SHM. in the experiment, the mass was suspended from a spring and allowed to oscillate vertically. Under these circumstances the mass is subject to gravitational force. Why doesn't gravitational force influence the results? (hint: the total force on the mass can be written as F = -kx-mg. Show that including the the weight of the mass can still result in the equation F=-Kx by changing the equilibrium point for the spring and making a variable change for the displacement of mass