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SAI INTERNATIONAL SCHOOL
                                                         Class 7
                                                     Lesson Notes
                                                   Subject-Physics
                                     CH: Light and Associated Phenomena
                                   Subtopic- Plane Mirror & Types of Image

                       Plane Mirror
                       It is a flat reflecting surface which reflects all the light falling on it.
                          Types of images
                           There are two types of images
                                      1.  Real image
                                      2.  Virtual image
                          Real image
                             The image which can be obtained on a screen is called a Real image.
                             It is always inverted.
                           Ex: Image formed by convex lens is real when object is kept far away from it.
                          Virtual Image
                             The image which cannot be obtained on a screen are called Virtual image.
                             Virtual image is always upright and erect.
                           Ex: Image formed by a plane mirror.
                         Characteristics of image formed by a plane mirror
                          An image formed in a plane mirror shows the following characteristics
                            Virtual, and erect (upright).
                            Size of image is same as the size of object.
                            Image distance is same as object distance from the mirror.
                            Image is laterally inverted.
                       Lateral Inversion
                          It is the phenomenon due to which right of the object appears to be
                          left in the image and vice-verse.



















                          Application of lateral inversion
                          AMBULANCE:
                          AMBULANCE written backwards so that the driver in the other vehicle ahead
                          of the vehicle will see the laterally inverted image of it and quickly give way to
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