Refracting Telescopes

Focal length
1. The distance between the focus and the lens is the focal length
  1. The focal length of converging lens can be calculated
    1. Focus the image of a distant object onto a piece of paper
      1. Measure the distance between the lens and the paper
Lens in a refracting telescope
1. Objective lens
  1. Convex lens
  2. Creates an image
2. Eyepiece lens
  1. Convex lens
  2. Magnifies the image
Refraction
1. Light travels in straight lines
  1. Changes direction when it moves into a different material
    1. This change in direction is called refraction
      1. It happens at the interface between two materials
        A line at right angles to the interface is called the normal line
Refraction and wave speed
1. Refraction occurs because light travels at different speeds
  1. Moving from air to glass, light slows down and refracts towards the normal

Resource summary

	Created by spafferine1 almost 11 years ago