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1  化工裝置(上)








                              例題 1-3


                                        N                    dyne                    kg
                           ༊Ӌ 1 Pa(      2  )=             (     3  )=             (    f   )=
                                       m                      cm                     cm 2
                                             lb
                                       psi(    f   )f
                                             in 2

                                                        5
                            解          N       N      10  dyne       1 m
                                1 Pa(     )=1      ×            ×(          ) 2
                                      m 2      m 2      1 N        100 cm
                                                        5
                                           =1   N   ×  10  dyne   ×   1 m 2
                                               m 2      1 N       100  cm  2
                                                                      2
                                           =   10 5   (  dyne   )=10  dyne
                                              100 2  cm 2         cm 2

                                           =1   N   ×  1 kg f   ×(   1 m   ) =1   N   ×   1 kg f   ×   1 m 2
                                                                         2
                                               m 2   9.8 N      100 cm        m 2   9.8 N     100  cm 2
                                                                                                  2
                                                                           -5 kg
                                           =      1      (  kg f   )=1.02×10 (    f   )
                                              9.8Ò100  2  cm 2                 cm 2
                                                                       2
                                                                                       2
                                           =1   N   ×   1 lb f   ×  0.3048  m 2   ×(   1 ft   )    ∴ 1 lb =4.45 N
                                               m 2   4.45 N         1 ft 2      12 in              f
                                                                       2
                                           =1   N   ×   1 lb f   ×  0.3048  m 2   ×   1 ft 2
                                               m 2   4.45 N         1 ft 2     12  in 2
                                                                                  2
                                                                          -4 lb
                                           =   0.3048 2   (  lb f   )=1.45×10 (   f   )=1.45×10  psi。
                                                                                              -4
                                              4.45Ò12  2  in 2                in 2





                              例題 1-4


                           1 kg €ʮ˘ɢ=                      N€ˬ཭k                     lb €ᆼɢk
                                f
                                                                                         f
                                       dyne€༺ځk

                                                                     2
                                                      2
                            解   1 kg =1 kg×9.8 m/s =9.8(kggm/s )=9.8 N
                                     f
                                           kggm       2.2 lb        1 ft                    lb gft
                                     =9.8          ×        m   ×           ≒ 2.2×32.174(     m      )
                                              s 2      1 kg      0.3048 m                      s 2
                                                                     lb gft
                                     =2.2 lb   ∵ 1 lb =32.174          m s 2
                                              f
                                                          f
                                            kggm      1000 g      100 cm             5 ggcm
                                     =9.8           ×          ×           =9.8×10 (           )
                                              s 2      1 kg        1 m                   s 2
                                                5
                                     =9.8×10  dyne。


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            ʷʈༀໄ ɪ DI  JOEE                                                                                                   ɪʹ
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