PhysicsCode 5054
Thin lenses
What this topic asks you to be able to do
- Describe how a parallel light beam is affected by a converging thin lens and by a diverging thin lens
- Define the focal length, the principal axis and the principal focus (focal point), and use these terms
- Draw ray diagrams to show a converging lens producing real and virtual images, and know that a real image comes from rays that converge while a virtual image comes from rays that diverge
- Define linear magnification as an image's length divided by the object's length; recall linear magnification = length of image / length of object and use this equation
- Outline the way in which a single lens serves as a magnifying glass
- Draw ray diagrams showing how images are formed in a normal eye, in a short-sighted eye and in a long-sighted eye
- Describe how long-sightedness is corrected with a converging lens and short-sightedness with a diverging lens