How many images of a candle will be formed if it is placed between two parallel plane mirrors separated by 40 cm?

How many images of a candle will be formed if it is placed between two parallel plane mirrors separated by 40 cm?
Answer:
Infinite number of images are formed. One mirror will reflect and form the image on the other mirror. Now, this image acts as an object and again forms an image on the opposite mirror. This phenomenon goes on infinite number of times.