Page 22 - Hybrid PBD KSSM 2021 Tg 5 - Fizik
P. 22

Fizik  Tingkatan 5  Bab 1

                                   Lif                                 (ii)  Lif itu turun ke bawah
                                   Lift                                    The lift goes down
                                                                                              F = ma
                                                                                              mg – R = ma
                                                                                              R = mg – ma
                                                                                                = 50 × 10 – 50 × 4
                                              Mesin penimbang
                                              Weighing machine         a = 4 m s –2  R          = 300 N
                                                                                              Bacaan penimbang
                                                                                              Reading of the weighing
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                                                                                              machine
                                                                                     mg       = 300 N
                                                                       (iii)
                              Nota Visual                                                  F =
                              Gerakan Lif                                                  R – mg = m × 0
                              Motion of Lift                                               (halaju seragam, pecutan
                                                                                           sifar)
                                                                                           (constant velocity, zero
                                                                                           acceleration)
                                                                       4 m s –1   R        R = mg
                                                                                             = 50 × 10
                                                                                             = 500 N
                                                                               mg          Bacaan penimbang
                                                                                           Reading of the weighing machine
                                                                                           = 500 N

                    (f) Rajah  di  bawah  menunjukkan  satu  beban  4  kg  (i)     R
                        disambungkan dengan seutas tali kepada sebuah
                        blok logam  6 kg yang diletakkan pada sebuah                      T
                        meja melalui satu takal licin.                             6 kg
                        The diagram below shows a 4kg load connected by a rope to a 6   F R      T
                        kg metal block placed on a table over a smooth pulley.
                                                                                   W
                                        6 kg                                                   4 kg


                                                                                                B
                                                    4 kg
                                                                       (ii)  Blok 6 kg / 6 kg block
                                                                           T – F  = 6a
                        (i)  Lakarkan gambar rajah jasad bebas bagi troli      R
                           dan pemberat.                                   T – 10 = 6a
                           Sketch the free body diagram of the trolley and the load.  T = 6a + 10 ....... (1)
                           W = berat blok logam                            Beban 4 kg / 4 kg load
                              the weight of the metal block                B – T = 4a
                           R  = tindak balas normal ke atas blok logam,     40 – T = 4a
                              normal reaction on the metal block           T = 40 – 4a ..... (2)
                           F   = daya geseran                              Menggantikan (1) ke dalam (2), / Replace (1) into (2)
                            R
                              friction force                               6a + 10 = 40 – 4a
                           T  = tegangan tali                              10a = 30   –2
                              tension of the string                        a = 3.0 m s

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         Bab 1.indd   10                                                                                           11/19/21   4:05 PM
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