Understanding the Concept

* Index of Refraction (n): This is a measure of how much light slows down when it passes from a vacuum into a medium. A higher index of refraction means the light slows down more.

* Speed of Light in a Vacuum (c): This is the fastest speed light can travel, approximately 299,792,458 meters per second.

* Speed of Light in a Medium (v): This is the speed of light in the material (in this case, glass).

The Formula

The index of refraction is calculated as:

n = c / v

Calculation

1. We know:

* Light travels 15 times faster in a vacuum than in glass, so v = c / 15

2. Substitute into the formula:

* n = c / (c / 15)

3. Simplify:

* n = 15

Answer

The index of refraction for glass in this scenario is 15.0.