# How Does Converging Lens Affect Focal Length

1480 Words6 Pages
Liam Stephenson controlled assessment Introduction In my course work I will be looking at how the thickness of a converging lens affects the focal length. The factors involved in this experiment are: light, lens curvature, refraction and thickness of the lens, these will determine the focal length; the focal length is the length between the focus and the lens. Light-visible light is an electromagnetic wave in the electromagnetic spectrum The speed of light depending on the medium it is in, for example the speed of light is 300,000 km/s however when light travels through other medium such as water or glass the speed of light is slowed this is because water and glass is denser than a vacuum of air. Due to it being more dense and a change in speed, the direction of the wave will change this is…show more content…
All lenses have a principal axis which is a line which passes through the middle of the lens. The focal points of all lenses are in front and behind the lens and are where the light rays initially parallel to the principal axis meet. This directly affects the focal length. Factors the affect focal length | How it affects focal length | Thickness | The thicker the lens is the more the light will be refracted creating a shorter focal length. | Medium | Light travels at different speeds in different mediums, as they can be more or less dense. This means that the refraction and wave speed will be altered when it hits the lens. | Colour of light | Different colours of light have different wavelengths and frequencies causing them to refract different amounts at different focal points. | Material | Depending on the material depends on how much the light will refract, as if you used ice it would refract less increasing the focal length compared to glass as ice is less dense.