This book is delightful. Published in 1939 it really approaches concepts in a “straight” forward way!
There are four ways that light is bent:
- By gravitation: such as when it passes by a star.
- Reflection: when it bounces off of an object.
- Refraction: when it passes through a transparent medium to another, your feet in water for example.
- Diffraction: when it passes through a small opening or passes by a sharp edge.
Reflection is what allows us to see objects, and the part of the white light that does reflect is what gives us our color.
Diffraction is quite interesting because it is what allows a “pin hole” to produce an image on the back wall of a dark room for example, and it is also why using small apertures on lenses causes a less sharp image. Geeky stuff but interesting!