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WORKSHOP CALCULATION & SCIENCE - CITS




                                       =   (D + d) (D - d) h

           Total surface area of hollow cylinder = Inner + outer curved area + area of top and bottom circular part

             TSA :  2 Rh + 2 rh + 2 (R² - r²)
           R = outer radius
           r = inner radius
           D = outer diameter

           d = inner diameter
           h = height of cylinder
           t = thickness
                      D - d
           Mean dia =
                        2
           If thickness given then:

           Volume of hollow cylinder = p x mean dia x thickness x height
           Finding out volumes of solids
           The space occupied by a body is known its volume. The volume of a body indicates the capacity to hold substance
           in it.
           The general form of Lateral surface area Total surface area  and Volume is:
           Lateral surface area        = perimeter of the base x height
           Total surface area          = LSA + 2 (base area)
           Volume                      = Area of base x height
           Important and commonly used solids are described below one after another:

           Cube
           1  Find the diagonal, lateral surface area,, total surface area and volume of a cube of side 4.5 cm.
                                         side a       = 4.5 cm

                                         diagonal d   =    a unit
                                                      = 1.732 x 4.5
                                                      = 7.794 cm
                                               L.S.A   = 4a²  unit²
                                                      = 4 x 4.5 x 4.5

                                                      = 81 cm²
                                               T.S.A   = 6a² unit
                                                      = 6 x 4.5 x 4.5
                                                      = 121.5 cm²

                                               V      =  a³ unit³
                                                      = 4.5 x 4.5 x 4.5
                                                      = 91.125 cc.









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                                            CITS : WCS - Electrical - Exercise 6
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