Both a mirror and a page of the book reflect light. you can see an image in a mirror but not in the book. why? choose any two objects that can produce an image.

A mirror reflects light when the atoms in a mirror catch the light and throw it back. the image what we see in a mirror is not what it's there but our brain tells us to think so. a book has trillions of irregularities present in them. for our image to be seen, it should be a polished surface, a mirror is a highly polished surface but a book is not polished. it also depends upon the material being used.

If an object is moving or in motion

therefore, the efficiency is: