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Fundamentals of Stress and Vibration                1. Mathematics for Structural mechanics
                 [A Practical guide for aspiring Designers / Analysts]
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                                            [Fig 1.77: cylinder develops to a rectangle]


                 Area of the developed cylinder =  H ∗ 2πr
                                                        2

                The sum of the developed cylinder area and that of the cone will give us the total material area.

                  π r + r   ∗ S  +  H ∗ 2πr
                                          2
                         2
                     1

                ‘S’ is the slant height of the frustum of the cone, as shown in [Fig 1.78], and is given by:















                                       [Fig 1.78: slant length (S) of the frustum of the cone]

                We have calculated the area of the sector/frustum of a cone to be:   π r + r   ∗ S
                                                                                       2
                                                                                  1
                Replacing the value of ‘s’ from [Fig 1.78] in the above expression, we get:

                 π r + r   ∗  H +  r − r
                                            2
                                2
                         2
                    1
                                     1
                                          2

                The total area  =   π r + r   ∗  H +  r − r     +  H ∗ 2πr
                                                 2
                                                             2
                                                      1
                                          2
                                     1
                                                                         2
                                                           2

                              QP No. SSC/Q4401, Version 1.0, NSQF Level 7, Compliant with Aero and Auto Industries,   Page 79
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