1. The problem statement, all variables and given/known data Two plain mirrors are put parallelly and 20 cm from each other. A source of light is put between the mirrors, 5 cm away from one. Find the distance from the mirrors of 4 first reflections. 2. Relevant equations a1=a2 The distance of the object from the mirror and the reflection from the mirror is equal. 3. The attempt at a solution http://s32.postimg.org/507dau85h/image.png is it right?