* Mirrors: A periscope has two mirrors placed at a 45-degree angle. The first mirror is positioned at the top of the periscope, angled to reflect light coming from above. The second mirror is placed at the bottom, angled to reflect the light back up to the viewer's eye.

* Reflection: When light strikes a mirror, it bounces off at the same angle it hit. This is called the law of reflection.

* Path of Light: The light travels in a straight line until it hits the first mirror. The first mirror reflects the light at a 90-degree angle, directing it down the periscope tube. This light then hits the second mirror, which again reflects it at a 90-degree angle, sending it back up to the observer's eye.

In summary: The two mirrors in a periscope work together to change the direction of light, allowing you to see objects that are above or below your direct line of sight.

Here's an analogy: Imagine a periscope as a long, narrow box with a mirror at each end. You look into one end of the box, and the mirror reflects your view to the other end. The mirror at the other end then reflects the view from the opposite direction back to you.