STEAM with Dad

Learning about lenses , refraction and optics in general has now enabled me to make my own telescope. I wanted to build one because I have always loved space and astronomy. Another day I must tell you about a hobby of mine, launching water rockets.  There are two main types of telescopes: refractors (made out of lenses) and reflectors (use mirrors too). Galileo Galilei made one of the first refractor telescopes and Isaac Newton made the first reflector. The one I built is a refractor, which is a bit cheaper to build.  How it works In this diagram you can see that the telescope has two lenses: The first is called the "objective". The function of the objective is to create an image with the light comes from the celestial body. The light rays come in parallel because the object is very far away. This means the image forms in the focal point. The image is inverted though. The second lens is called the "eyepiece" and it typically has a much smaller focal length. The eye...

Today I am going to tell you what lenses are, how they work and many more things. Let's dive in! A lens is an optical device with at least one curved surface to focus or disperse light beams by means of refraction.  Some of you may be wondering why I am talking about lenses. Well, it is because of how common they are, for example lenses are used in microscopes, telescopes, cameras, and even your Granma's reading glasses. So, now that you know what lenses are I can teach you how they work.  In the previous blog post we saw the light moving from air to water. The surface between the two media was flat but the surface of the lens is curved. We can use Snell's law if we think of a curve as  a big series of tiny flat lines one after the other.  For example in my diagram below I have drawn a plano-convex lens and three light rays. First, they go through the flat face of the lens. Snell's law predicts that they will go straight through because the sine of 0 degrees is 0 The...