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126                                                        Chapter 2
         Problems


         Problem 2.1
             For a  constant rectangular  cross-section microcantilever, the  tip  force
         that corresponds to the tip deflection and slope can be expressed as  shown in
         Eq. (2.21)  with the  stiffnesses being:
                         However, one can approximate the  individual compliances
         as being the  algebraic  inverses of the corresponding stiffnesses as:
                                                Determine the maximum  relative
          errors between the force   calculated according to the first set of stiffnesses
          and the same force calculated by the second set of stiffnesses, when
                                              and                    and



          Answer:
             Maximum relative error = 50%


          Problem 2.2
             Design a  solid  rectangular  microcantilever  such that its  linear bending
          stiffness about the bending-sensitive axis,   is 16 times smaller than the
          other linear  bending stiffness   and 100  times  smaller than  the  axial
          stiffness

          Answer:






          The thickness can be chosen arbitrarily.

          Problem 2.3
             Determine the mass  that  adheres to  a  constant  rectangular
          microcantilever  with                               and  E =  150 GPa
          assuming the  deposition produces no  torsion of the microcantilever. Known
          are also the tip displacements    and

          Answer:



          Problem 2.4
              A circularly-filleted  microcantilever is  used in  a  magnetic  writing
          application. Find the maximum values of the tip force components   and
              considering that      is  negligible. The  parameters  defining the
          microcantilever are: E = 200 GPa,                             and
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