Two springs of flexural rigidity EI makes an angle of 30 ° with the horizontal line and support a rigid square plate of length 2l1 (Fig. P4.7). The structure and a slender fixed - fixed beam on a wafer are released when the surface micromachining has been completed. If the residual stress in the released fixed - fixed beam is measured as σr, find the displacement of the lower right corner of the square plate during the release period.
