By: Yelyzaveta Lapina,

Damien Uthayakumar,

Mohsen Najafi,

John Unsal,

Francisco Xabier Ugarte Cavagnaro

The purpose is:

to find out the path of light when it passes through a diverging lenses

To figure out how the three principal rays will react with a diverging lens.

Ray box

Blank white sheet of paper

Diverging lens

Ruler

Set up the apparatus to find the focal point (F) of the lens, place the ray box on another side of the lens to find the focal point (F’)

Adjust the ray box to produce a single ray and direct it towards the lens, so that the ray:

• Points in the direction of the secondary focal point of the lens

• Is parallel to the principal axis • Passes through the optical centre of the

lens Record the results

Diverging Lens

Focal length is 7 cm

Diverging Lens, First principal ray

Ray is parallel to the principal axis and is refracted in such way that it appears to come from the lens’s principal focal point (F)

Diverging Lens, Second principal ray

Ray points in the direction of the focal point and is refracted parallel to the principal axis

Diverging Lens, Third principal ray

Ray goes through the lens’s optical centre and travels straight through

The lens consists of a transparent object that has at least one curved surface and controls the direction of the light rays passing through it.

Lens is said to be diverging when parallel beams of light enter it diverge from the secondary focal point

When light passes through the concave lens, refracted rays diverge and do not intersect each other, diverging rays appear to come from the focal point.

To find the image of the object it’s required to shine 3 principal rays through the lens.

The images are formed by help of these principal rays in the lens

In order to figure out if the lens is symmetrical, shine incident rays on both sides of the lens, and observe if both focal lengths are the same.

The lens which was used in the experiment was symmetrical

Lenses and principal rays are used in technology and they many applications:

Principal rays are used in order to get an image of the object, while using the magnifying glass, microscopes, telescopes or photo cameras.

Errors: The rays from the ray box weren’t

exactly parallel to each other, which changes the results.

The sheet of paper shifted slightly during the experiment altering the possible results.

The priority was to find out the path in which the light beam takes when it passes through a concave lens

In concave lenses refracted rays diverge Using the principal rays of the lens, it’s

possible to find the image of the object, when the principal rays intersect they form an image