Page 173 - MathGPT_V1.0_C5
P. 173

D:\Surender Prajapati\Books Final_CBSE and ICSE\ICSE\Preparatory_Stage_Maths-5_(31-10-2023)\Open_Files\CHAP_08
              \\November 3, 2023 12:44 PM   Surender Prajapati   Proof 5   Reader _________________________   Date: ___________________74













                                    Original posi�on  Half turn       Original posi�on   Half turn
              Some shapes look same even if we give them a half turn.








                                   Original posi�on   Half turn        Original posi�on    Half turn
              Rotational Symmetry

              Rotational symmetry of a figure occurs if it appears the same two or more times during a
              complete rotation of 360° about a fixed point.
                         Q                    P                   S                   R                   Q



                   R            P      Q            S      P            R       S           Q       R            P


                         S                    R                   Q                   P                    S
                                         Position after      Position after       Position after      Position after
                                           90° turn            180° turn           270° turn            360° turn
              The figures that possess rotational symmetry need not necessarily possess line symmetry.







                               Original           Position after       Position after       Position after
                               position             120° turn            240° turn            360° turn
              Here, the given shape possesses rotational symmetry but no line symmetry.



                       Think and Answer
                    What time will be in the clock, if the minute hand take:
                        1
                    1.    turn?           ______________
                        4
                        1
                    2.    turn?           ______________
                        2


                       Practice Time 8B


                1.   Look at each pair of letters. Identify in which pair the second letter slides, flips or
                    turns.
                    (a)                           (b)                          (c)





              Mathematics-5                                                                                          171
   168   169   170   171   172   173   174   175   176   177   178