As light from an object refracts as it passes througha a converging or diverging lenses it bends, allowing up to see images.
An Introduction to Lenses
This short video covers some of the terminology you need to know when learning about lenses over the next few videos.
Converging vs Diverging
Converging (convex) and diverging (concave) lenses explained.
Power of a Lens
The more powerful a lens is, the more bending ability it has.
Magnification of a Lens
The magnification can be calculated by dividing the image height by the height of the object. We can also calculate it as the ratio of 'v' to 'u'.
The Lens Equation
You may be familiar with the equation linking 'f', 'u' and 'v'. In this videos I show you where this equation comes from.
Images in a Converging Lens - Part 1
When an object is far away from the lens (greater than the focal length) then the image will appear upside down. In this video I show you how to construct a ray diagram to find out where it will form.
Images in a Converging Lens - Part 2
Object closer than the focal length will appear enlarged and 'virtual'. this is how.
Images in a Diverging Lens
Finally, this is how objects appear when viewed through a diverging lens.