The structure of the periscope explains why it can be used to see over obstacles.Explain the function of the two mirrors in the periscope.

A periscope works on the principle of reflection of light. The two mirrors in a periscope serve a crucial role in this process.

1. The first mirror: This mirror is placed at the top of the periscope, angled at 45 degrees. When you look through a periscope, the light from an object strikes the first mirror. Because the mirror is angled, it reflects this light down the periscope tube.

2. The second mirror: This mirror is placed at the bottom of the periscope, also angled at 45 degrees. The light reflected from the first mirror strikes the second mirror and is again reflected, this time into the viewer's eye.

The two mirrors in a periscope are positioned parallel to each other, and their 45-degree angles mean that the light path is essentially a 'Z' shape. This is what allows you to see over obstacles when looking through a periscope. The light from the object travels into the periscope, is reflected twice, and then travels into your eye, allowing you to see the object.