Radian and Steradian
Radian and Steradian In this post, we'll discuss the concept of angles and the methods for measuring them. This will be a journey based not on abstractness but rather on intuitive rigor . By this, I mean, we shall develop the concepts from the known fundamentals, and at each step, ask if we can convince ourselves that what we are doing makes sense to the common intellect. We'll start by defining an angle and studying its geometry. Then we'll try to understand the different units employed to measure this with an emphasis on radian. Finally, we'll also introduce the concept of the solid angle and steradian. So let's begin our journey! An Angle: Defining an angle is as difficult as defining a line. Ask yourself, "Can I write a statement that completely encompasses the concept of line?" You may call it, like Euclid said, a 'breadthless length'. But then what do you mean by length? Can you really explain something like length without the ...