Consider a thin homogeneous plate of mass M that lies in the x1-x2 plane with its center at the origin. Let the length of the plate be 2A (in the x2-direction) and let the width be 2B (in the x1-direction). The plate is suspended from a fixed support by four springs of equal force constant K at the four corners of the plate. The plate is free to oscillate but with the constraint that its center must remain on the x3-axis. Thus, we have three degrees of freedom;