Finding the Focal Length of a Given Convex Lens Aim: -
To find the focal length of a given convex lens.
Apparatus: -
Convex lens Metre rule
Screen Candle
Matches Wooden blocks
Theory:-
In this experiment the focal length of a lens is found out. The focal lens of a lens is the distance from the principal focus to the optical centre. It is the point where the image comes into focus when seen though the lens. The focal length of a lens depends on the curvature of each surface. So the more highly
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The independent variable is the distance d, the distance between the screen and the illuminated object.
The controlled variable is the intensity of the illuminated object and the focal length of the lens
Procedure
1. Place the illuminated object at a distance of 50 cm from the screen and set up the apparatus as shown in the figure above.
2. Now place the lens somewhere close to the screen and see in which position of the lens does the illuminated object comes into focus on the screen.
3. Mark this position as L1 and record its distance from the illuminated object.
4. Now place the lens somewhere close to the illuminated object where the object comes into focus on the screen.
5. Mark this position as L2 and record its distance from the illuminated object.
6. Repeat the experiment for values ranging from 50 cm to 100 cm.
7. Tabulate six sets of the values of d, L1, L2, l and l 2/d.
8. Plot a graph of l 2/d against d.
9. From the graph, find the y- intercept of the graph and
The fair testing will be carefully checked so the results do not come out to be void. The light intensity will be changed for it is the only variable used in the experiment. Though the temperature, watt of the bulb, amount of water, size of the plant and posit...
Variables Independent variable: The independent variable is what you are going to do. to change throughout the experiment; in this case it is the light.
The objective of the experiment is to determine whether subjects with hyperopia or myopia have the same degree of lateral peripheral vision. Hyperopia, or farsightedness, occurs if a person’s eyeball is too short for the cornea, or if the cornea has to little curvature so that the light refracting is not focused in the eye correctly. This results in having trouble focusing or concentrating clearly on an object that are near to the person (http://www.aoa.org/patients-and-public/eye-and-vision-problems/glossary-of-eye-and-vision-conditions/hyperopia ). Myopia, or nearsightedness, occurs when a person’s eyeball is too long or their cornea is curved too much. This leads to an incorrect refraction of the light and causes blurred vision when focu...
Y = sales of firm, X = average height of employees, α = intercept of the regression line,
The dependent variable that will be measured is the height at which the ball bounces back. The control variables that will need to be kept constant if the results are to be as accurate as possible are. 1. What is the difference between a. and a. The weight of the ball; we will use the same ball throughout the experiment to ensure that the results are as accurate as possible.
My interest into becoming an optometrist had begun when I was in high school; it happened in an unconventional way. It was not through watching videos, or someone explaining to me what optometry was, but rather, seeing the power of it firsthand. There was a point in my life where I felt emotions that I was unable to comprehend at the time. Seeing a family member on an operating table was the most petrifying moment that I have gone through, especially when the person on the table was my father. My father had to get a chalazion removed from his right eyelid. The doctor told my family that my father would be susceptible to certain health risks because of his diabetes and the severity of his cyst. This procedure was the hardest thing I have had to deal with in my life because it made me feel helpless. Usually, when my dad needs help he always asks me, but this time I could not do anything. It is interesting to think that something so small had such a big affect on my life.
It is a daily ritual...wake up, eat, shower, contacts, class. I do this every morning, however I have never stopped to think, "Why?"
Change (y = x2 – 6x + 11) to (2x = x2 – 6x + 11) by substituting 2x by y and solve the quadratic equation. The solution for the equation one will give the points (x1, y1...
...isual attention within and around the field of focal attention: A zoom lens model. Attention, Perception, & Psychophysics, 40(4): 225-240.
Of the multitude of careers in the health care industry, optometry has one of the greatest outlooks with regards to future employment and need, largely due to the health care requirements of the aging population. Optometry has several different modes of practice to choose from, including private practice, commercial, hospital, and community health centers to name a few. To further investigate private practice optometry, I shadowed Dr. Stuart Anderson in Gladstone, Missouri. Dr. Anderson is a member of the first graduating class of the University of Missouri Saint Louis College of Optometry and has been practicing optometry for 32 years. He owns a successful private practice, Anderson and Nutt, and throughout his career, has established himself
To focus the camera, place the very edge of the aluminum frame guide to what you wish to photograph,
The eye is an extremely diverse organ, ranging in complexity across and within animal phyla. Here, a comparative approach is taken to outlining the diversity of the eye forms within vertebrates and invertebrates. The eye morphology of a variety of organisms was examined. Eye function, and placement on the body was also considered. Here, variation in eye form is discussed in relation to the environment the organism is adapted to. It is shown that an organisms eye morphology functions optimally for the ecological niche it occupies. Evolutionary analysis is used to account for the emergence of the different eyes. Convergent evolution is used to justify the similarities in eye types seen in organisms of different species. This analysis begins with the simplest of eye forms composes of single cells, present in the zooplankton larvae. Such primitive forms are identified in mollucs, annelids, cnidarians, and are then compared to more advanced eye forms contain lenses. This comparative approach provides a breadth of examples of vertebrates and invertebrates, making visible, the diversity of eye morphology within the animal kingdom.
the distance from the light source to the plant. Output - The rate of photosynthesis is to be measured by counting the bubbles of oxygen produced by the plant every two minutes, and therefore finding the rate of photosynthesis. Control - The amount of water available to the Elodea will stay the same. same level as the 400 cm3 beaker. The colour of the lamp will stay the same (yellow) as to plants Chlorophyll easily absorbs blue light.
Due to the nature of a sphere, the light will actually not all be focused exactly towards the focus. Instead, light near the edge of the lens will be focused just before the focal point on the optical axis, and light near the center of the lens will be focused just after the focal point on the optical axis. This produces an image that looks blurry or “out of focus”. The simplest way to prevent spherical aberration is to rather than using a spherical lens, use a parabolic lens. Parabolic lenses have exactly the right shape as to focus the light to a central point. The downside of this is that parabolic lenses are significantly more challenging to make than spherical lenses, so for most cheaper telescopes, other methods are used. Some telescopes eliminate spherical aberration by using two different lenses that have equal, but opposite spherical aberration, so that the aberration cancels itself out and the image appears
Thanks to his studies, especially after the translation of Kitâb al-Manâzir (The Book of Optics), many scholars and scientists were inspired. Later European scholars were able take what he had discovered and further our knowledge about cameras and optics in general. Alhazen’s creation of the pinhole camera is the reason why cameras and other important inventions were created, such as eye-glasses, magnifying glasses and telescopes were created, as scholars and scientists knew how images are reflected in our eyes. He especially influenced Isaac Ne...