The focal lengths of unknown lenses are determined by measuring
the distances of image and object and by Bessel's method. Simple
optical instruments are then constructed with these lenses.
- To determine the focal length of two unknown convex lenses by
measuring the distances of image and object.
- To determine the focal length of a convex lens and of a
combination of a convex and a concave lens using Bessel's
- To construct the following optical instruments:
a) Slide projector; image scale to be determined
b) Microscope; magnification to be determined
c) Kepler-type telescope
d) Galileo's telescope (opera glasses).
What you can learn about
- Law of lenses
- Focal length
- Object distance
- Path of a ray
- Convex lens
- Concave lens
- Real image
- Virtual image
- understand a basic optical component: the lens
- learn how common optical instruments work
- geometric optics in a nutshell