Two plane mirrors are placed parallel to each other at a distance L apart. A point object O placed between them at a distance L/3 apart from one mirror. Both mirrors form multiple images. The distance between any two images cannot be.A) 3L/2B) 2L/3C) 2L

I  guess the answer should be 3L/2. since they are parallel mirrors, the total images formed is infinite (which is already in the question) and as it’s a plane mirror the image distance and object distance will be equal. so L/3 for one mirror menas 2L/3 from the other mirror. the image formed by L/3 object is L/3 for one mirror behind it and for the other mirror since it will act as an object at 2L/3 it forms image at 2L/3. so adding L/3+L/3 one image and 2L/3+2L/3 (the other image) is 2L. similarly if you consider two images by the same mirror it will be L/3+L/3 =2L/3 in one case and in the other case 2L/3+2L/3 =4L/3. thus i guess it could never be 3L/2. hope it helps :)