Opticss Essay, Research Paper
Purpose: To analyze features of a convergence lens and the images they create. Besides to analyze the focal length and how the focal point point may be found and developing regulations for turn uping an image via ray drawings and the intersection of beams. Chromatic aberrance will besides be explored and why it happens.
Theory: Both lenses and mirrors have a rule axis, yet a lens has two focal points as opposed to a mirror that has merely one. When sing meeting lenses, the primary focal point ( PF ) can be found on the opposite side of the lens in respects to the visible radiation. The secondary focal point ( SF ) being on the same side as the light beginning. Focus points on thin dual convex lenses are located at either side of the lens, measured from the center of the lens itself ( see below ) . Chromatic aberrance is a job of meeting lenses that will besides be explored in this experiment. A description of each image produced will besides be given ( attitude, type, magnification and location ) .
Apparatus: The chief tools ( setup ) used in the experiment consist of a beam box containing cards which allow one, two, three or four beams onto a sheet of paper at a clip so that rays way from the box to the mirror will be able to be traced. Besides two ( 2 ) different types of meeting lenses, one being cylindrical while the other being spherical, the difference being that the spherical one is used for sing, the cylindrical 1 for usage with the beam box. These lenses are one of many different kinds of lenses in the & # 8220 ; lens box & # 8221 ; . The usage of a swayer would besides be helpful so that accurate measurings may be taken.
Method:1. A cylindrical lens was placed on paper and traced about, a chief axis was drawn doing certain that it & # 8217 ; s at rights angles to the lens. The beam box was switched on ( exposing merely one beam ) and lined up parallel to the rule axis, a grade where the beam leaves the box was made every bit good as where it hits the lens ( on both sides ) and where the beam bisects the rule axis. After this, the beam box was removed and utilizing a swayer, beams were
accurately drawn. The focal point point ( degree Fahrenheit ) was measured to be of length 7.3cm ( 7.25 ) .
2. The lens was replaced back on a sheet of paper with beam box breathing three beams, the in-between beam lined up on the rule axis, Markss were made where the beam & # 8217 ; s intersected at on the rule axis and this was measured to be the primary focal point point.
3. Step two was carried out but on the other side of the lens and the secondary focal point point was located and marked in.
4. The beam box was so placed on the original side of the lens and three separate beams where directed towards the lens to set up the undermentioned regulations:
a ) A beam directed parallel to the chief axis will be directed through the primary focal point.
B ) Angstrom beam through the secondary focal point will be refracted out parallel to the chief axis.
degree Celsius ) A beam directed through the center of the lens will be directed out parallel to it & # 8217 ; s original beginning.
5. A beam was so directed at the outer border of the lens and the beams where directed merely inside the focal point point. Chromatic aberrance took topographic point in this instance where beams of different colourss were refracted out of the lens.
6. A technique was developed for specifying the focal point of spherical of & # 8220 ; sing & # 8221 ; lenses. Below are the instructions.
Topographic point the beam box, lens and screen on a parallel axis ( chief axis ) .
Switch over the beam box on and travel the lens backwards or forwards until the image goes to a individual point on the screen and becomes reverse if the lens is moved any farther. Measure the distance from the lens to the beam box. This is the focal length.
As the lens passes the focal length the image becomes inverted ( turned upside down ) .
7. When the lens is held at arm length to see objects around the room three features can be seen from the image. The image is unsloped, reverse and the magnification decreases.
8.a ) do & gt ; 2F & # 8211 ; inverted, existent, reduced, beyond F and 2F.
B ) do=2F & # 8211 ; inverted, existent, same size, located at 2F.
degree Celsius ) 2F