Lens Definition and 787 Threads
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Understanding Diverging Lenses: Homework Statement and Solution Attempt
Homework Statement How do you know this? if anyone can help, it would be greatly appeciated! Homework Equations The Attempt at a Solution Homework Statement Homework Equations The Attempt at a Solution- Aikenfan
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- Lens
- Replies: 6
- Forum: Introductory Physics Homework Help
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Finding Distance Between Lens Positions: Solve for a
Homework Statement The distance between an object and its image is fixed at 40.0 cm. A converging lens of focal length f = 4.2 cm forms a sharp image for two positions of the lens. What is the distance a between these two positions? Homework Equations 1/p + 1/q = 1/f The Attempt at...- dmolson
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- Lens
- Replies: 1
- Forum: Introductory Physics Homework Help
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Lens Experiment: Understanding b Values
I need a little help with a laboratory class I had about lens. Experiment: We had a light source with a draw of an arrow on it, this light go through a lens of +100 mm (focal length) and a surface on the other side of the lens were we can see the arrow on it. We put the light source at...- Link-
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- Experiment Lens
- Replies: 6
- Forum: Introductory Physics Homework Help
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Find Largest Focal Length Lens for Photo of Poster - 2.79mm
Homework Statement You take a picture of a poster on the wall of a room and maximum distance you can get from the picture is 3.1 m. The poster is 0.8 m wide and 1.2 m tall and you want it to fit in the 24 x 36 mm frame of the film in your camera. What is the largest focal length lens that...- deenuh20
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- Focal Focal length Length Lens
- Replies: 2
- Forum: Introductory Physics Homework Help
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How does a converging lens create the Fourier transform of an aperture?
Hello, does anyone know how a converging lens forms the Fourier transform of an aperture when the obs. screen is at distance=f? If each point emits a spherical wave, the lens should make it then parallel and the FT should be the interference resulting from that. However, if we decompose... -
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Solving Final Image Formed from Convex and Concave Lens
Homework Statement An object is placed 6 metres from a convex lens of focal length 30cm. A concave lens of focal length 5cm is then placed 20 cm from the concave lens, on the side distant from the object. Determine the position, magnification and nature of the final image formed (to solve...- Brewer
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- Concave Concave lens Convex Final Image Lens
- Replies: 9
- Forum: Introductory Physics Homework Help
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What Image Forms with an Object Two Focal Lengths from a Diverging Lens?
Homework Statement 2. An object is placed two focal lengths from a diverging lens. What type of image forms? What is the magnification? Where is the image? Homework Equations 1/f = (n-1)(1/r1-1/r2) The Attempt at a Solution a) Virtual Image b) m = 1 c) the image is on...- sapiental
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- Image Lens
- Replies: 1
- Forum: Introductory Physics Homework Help
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Thin Lens Equation - How to Solve for the Position of a Converging Lens
Homework Statement 3. A converging lens has a focal length of 10 cm. A screen is placed 30 cm from an object. Where should the lens be placed, in relation to the object, to produce a focused image?Homework Equations 1/do + 1/di = 1fThe Attempt at a Solution Do can not be greater than 2F...- bananan
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- Lens Thin lens
- Replies: 9
- Forum: Introductory Physics Homework Help
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Can anyone tell me where to buy an off-axis collimating lens?
I'm tired of looking for mirrors to do my applications, so I was wondering if anyone knows where to find an off-axis collimating lens. I haven't been able to find one myself, not even in edmund optics or other major suppliers. If anyone does know, can you tell me where to get it and the place... -
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Reason for Different Focus Distances in Converging Lens Lab
we used a converging lens and a screen with white paper in front of a window to form an image of a distant tree outside. This was about 15cm. When we used an optics bench and a candle to figure out the focus, it was 16.3cm... What would be a reason for the difference in the number?- jnimagine
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- Converging Lab Lens
- Replies: 12
- Forum: Introductory Physics Homework Help
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Why Did a Real Image Appear at 136cm in a Converging Lens Experiment?
hi i posted the same sort of question a few times before but this time it's a little different we did an experiment with a converging lens and a candle to find an image. When the candle was placed at the focal point, which was 16.3cm, an image appeared at 136cm. I know in theory, no image...- jnimagine
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- Converging Experiment Lens
- Replies: 1
- Forum: Introductory Physics Homework Help
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Converging Lens Focusing: Finding the Optimal Lens Position
I'm having a little problem with this question.. my brain is too small. "A converging lens has a focal length of 10 cm. A screen is placed 30 cm from an object. Where should the lens be placed, in relation to the object, to produce a focused image?" I've started with the formula 1/do +...- bananan
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- Lens
- Replies: 11
- Forum: Introductory Physics Homework Help
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What is the magnification problem with two lenses?
Here is the problem I am working on: Two lenses that are L = 38 cm apart are used to form an image, as shown in Figure 26-52. Lens 1 is diverging and has a focal length f1 = -7 cm; lens 2 is converging and has a focal length f2 = 16 cm. [a] Determine the distance from lens 1 to the final...- FlipStyle1308
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- Lens Magnification
- Replies: 21
- Forum: Advanced Physics Homework Help
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Solving the Biconcave Lens Problem with Reflection and Refraction
Here's the problem: Here's what I understand: I know what a biconcave lens looks like, and how it behaves (for the most part). Of course I know that the index of refraction is ~1.00. And since the radii are equal that makes the equation somewhat easier. The thick lens equation is...- NutriGrainKiller
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- Lens Reflection Reflection and refraction Refraction
- Replies: 1
- Forum: Introductory Physics Homework Help
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Measuring refractive index of liquid using lens and mirror
hi i've got to do measure hte refractive index of a liquid with mirror and lens first of all how can i measure hte refractive index of air in this way? i don't get how i can do this, please explain :| and then for the liquid, I've been told to put the liquid over the mirror and then the...- blackcat
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- Index Lens Liquid Measuring Mirror Refractive index
- Replies: 24
- Forum: Introductory Physics Homework Help
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Object Distance From Converging Lens for 1% Focal Length Difference
How far away from a converging lens must an object be ( in terms of focal length, f ) so that the difference between the image distance and the focal lengh is 1% of the focal length? I tried to translate the words into an equation based on the thin lens equation but i don't know if it is...- spoonthrower
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- Converging Difference Focal Focal length Length Lens
- Replies: 3
- Forum: Introductory Physics Homework Help
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Solve Thin Lens Equation: Diverging Lens, Virtual Image
I am stuck on this problem because it been like 6 yrs since i took geometry and its due by 9 am. please help! Derive the thin lens equation: 1/object distance + 1/ image distance = 1/focal length for a divergent lens, using a diagram of a divergent lens (hint: use similar triangles)...- spoonthrower
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- Lens Thin lens
- Replies: 2
- Forum: Introductory Physics Homework Help
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Question on light intensity at the focus of a lens.
From using a magnifying lens under the Sun, I gather it can focus all or most of the light impinging on its surface area to a small spot and that is how it is able to create a greater intensity light at its focus (disregarding absorption in the lens.) Correct? What portion of the total light... -
Is the Image Formed by a Concave Lens Real or Virtual?
# A convergent beam is incident on a concave lens as shown in figure. Which of the following is not correct? a) The image formed is real b) The image formed is virtual c) The image formed is erect d) The image formed is magnified I solved it in the following way: Let f be the focal...- Amith2006
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- Concave Concave lens Image Lens
- Replies: 3
- Forum: Introductory Physics Homework Help
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Focal length of plano convex lens
# Diameter of a Plano-convex lens is 6 cm and the thickness at the center is 3 mm. If the speed of light in the material of the lens is 2 x 10^8 m/sec, what is the focal length of the lens? I solved it in the following way: Let R be the radius of curvature of the convex surface. Given that AB...- Amith2006
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- Convex Convex lens Focal Focal length Length Lens
- Replies: 2
- Forum: Advanced Physics Homework Help
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Focal length of concave lens using convex lens
# A convex lens of focal length 10 cm forms a real image of an object placed at a distance of 20 cm from it. Midway between the convex lens and the position of the image a thin concave lens is introduced. The image formed now is at a distance of 5 cm away from the earlier position. What is the...- Amith2006
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- Concave Concave lens Convex Convex lens Focal Focal length Length Lens
- Replies: 3
- Forum: Introductory Physics Homework Help
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Convex Lens Image: Solve Problem & Describe Image
I have to complete a problem about locating an image for a convex lens but I'm having trouble with it. I tried it out, but I can't complete it. Can someone help please? Locate the image for the convex lens below. Use any two rays to do so. Give the characteristics of the image. I'm having...- Alain12345
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- Convex Convex lens Lens
- Replies: 4
- Forum: Introductory Physics Homework Help
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Solving Thin Lens Formula Problems
I have to complete a chart using the thin lens forumla. Can someone please help me out? I know that the formula is 1/f= 1/do= 1/di, but I don't know how to use it. Thanks.- Alain12345
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- Formula Lens Thin lens
- Replies: 10
- Forum: Introductory Physics Homework Help
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Calculating Lens Power: Q&A for Diopters
I have a question dealing with diopters. Q: Assume that the distance from the lens of your eye to the retina is 1 inch (in effect, the image distance). Calculate the power of the lens in your eye (in diopters) for both your far point and near point. The difference between these two lens powers...- nophun6
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- Lens Power
- Replies: 1
- Forum: Introductory Physics Homework Help
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Minimun lens size (in meters) that will permit just resolving 2 stars
I have really no clue on how to this:cry: please help!- cheez
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- Lens Stars
- Replies: 4
- Forum: Introductory Physics Homework Help
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Calculate a: Dist. b/w Lens Positions for 40 cm Object-Image Distance
The distance between an object and its image is fixed at 40.0 cm. A converging lens of focal length f = 3.62 cm forms a sharp image for two positions of the lens. What is the distance a between these two positions? Determine: The distance between these two positions a = ____cm Could...- matt85
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- Lens
- Replies: 2
- Forum: Introductory Physics Homework Help
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Anti-Reflecting coatings on a glass lens
heres the question: anti-reflection coatings on a glass lens (n=1.50) consists of a magnesium fluoride (n=1.38) film, the coating thickness is chosen to eliminate any back reflectionusing the ideas of destructive interference. What is the minimum coating thickness required to eliminate the...- BananaMan
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- Glass Lens
- Replies: 1
- Forum: Introductory Physics Homework Help
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What Is the Proper Sign Convention for a Virtual Image in Lens Calculations?
Here is the problem: A converging lens with a focal length of 12.0 cm forms a virtual image 8.00 mm tall, 17.0 cm to the right of the lens. I am supposed to find the position of the object. I tried using the lens eq. 1/s + 1/s' = 1/f where s is the distance of the object from the lens, s'...- ACLerok
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- Lens Light
- Replies: 6
- Forum: Advanced Physics Homework Help
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Optics: building a camera with quasi-hemispherical recording surface, what lens?
I make Daguerreotypes (http://en.wikipedia.org/wiki/Daguerreotype) and I have decided that I want to move from the standard flat-plane photography and make images on silver domes instead. I have domes that are 1.85" in diameter and I want to replicate the effect that a garden gazing ball gives... -
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How do I calculate the diameter of the sun's image using two lenses in optics?
Hi, I have an optics Q here I'm not quite sure about:- a.) An astronomers uses a single thin lens of focal length 0.5m to form a sharp image of the sun on a white screen. If the angular width of the sun is 0.5 degrees, what is the diameter of the sun's image. b.) At night the astronomer...- T7
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- Lens Optics
- Replies: 4
- Forum: Introductory Physics Homework Help
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How to Estimate Resolution with Given Lens Parameters?
Hey guys. I have a lens problem: A lens has a power of 300 dipoters, and a radius a of 2 mm. An object is located just beyond the focal length to get high magnification. The space between the object is filled oil with an index of refraction 1.4. Estimate the resolution for 500 nm light...- bemigh
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- Idea Lens
- Replies: 3
- Forum: Advanced Physics Homework Help
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Jupiter as a Gravitational lens?
Jupiter as a Gravitational lens?? I remember reading in a swedish science mag about a planed probe to the solar foci 550 AU from the sun. When there it would use the gravity lensing of the sun as a telescop. But getting a probe out there and the cost of the project seems like to much of a...- Azael
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- Gravitational Jupiter Lens
- Replies: 7
- Forum: Astronomy and Astrophysics
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Understanding the Lens Equation: Fish & Pattern Location
i just need a little help with a relatively easy lens question A small fish is cast into the center of a glass sphere of radius R=5 cm and n=1.5. Where will an observer see the fish? Where will the observer see a decorative pattern painted on the back side of a sphere? So, I thought I...- meadow
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- Lens
- Replies: 3
- Forum: Introductory Physics Homework Help
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Hyperbolic Lenses: Abberation-Free?
Are hyperbolic lenses free of abberation? -
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Optical Lens Selection for 612nm Laser Source
Hi, I'm trying to set up a lens system as follows: - Laser source 612nm - This passes through an apature to act as a spatial filter... - then through non-reflective glass onto a crystal of diameter upto 150um - the lens must then take the diffraction pattern from this crystal upto... -
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Normalizing Data from Lens Equation Lab
Can anyone explain how one would normalize data from a lab? We just completed the lens equation lab in class and part of the analysis is to include "normalized" virtual object data in the graph. There are only 4 measurements taken. Any feedback would be great! :shy:- wrkinhard
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- Data Lab Lens
- Replies: 1
- Forum: Introductory Physics Homework Help
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Digital video camera lens information
I am going be so pleased i f anyone can suggest a website where i can find information regarding the following topic: Digital video camera lens.do anyone know a website where i can download a short video regarding fiber optics.- ninaricci
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- Camera Digital Information Lens Video
- Replies: 1
- Forum: Materials and Chemical Engineering
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Easy way to remember imaging properties of lens?
Is there an easy way to remember what kind of images will be formed from converging/diverging lens depending on where you place the object relative to the focus? For instance, how to tell if the image is inverted vs. erect, real vs. virtual, smaller vs. magnified? I always have a hard time... -
Stargazing New 135mm/f2.8 Lens & Rig: My Experiences So Far
I bought a new toy to play with. It's a 135mm/f2.8 lens I found used at B&H Photo for $39. I cut a hole in the back lens cap, glued a t-thread spacer to it, and built a little piggy-back rig for it and my DSI. Its pretty heavy, so I was a little worried that my ETX wouldn't be able to handle...- russ_watters
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- Lens
- Replies: 3
- Forum: Astronomy and Astrophysics
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Lens Aberrations: 1st, 3rd & 2nd Orders Explained
I was doing some reading on lens aberrations and saw some referance to 1st and 3rd order aberrations. What are they and what is the differance? Are there and 2nd order aberrations? -
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At Center of Convex Lens & Glass Plate: What is Observed?
A convex lens is placed on a flat glass plate and illuminated from above with monochromatic red light. When viewed from above, concentric bans of red and dark are observed. What does one observe at the exact center of the lens where the lens and the glass plate are in direct contact.- skrewd1
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- Center Convex Convex lens Glass Lens Observed Plate
- Replies: 3
- Forum: Introductory Physics Homework Help
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Solving a Physics Problem: Inverted Image & Lens Separation
I have this Physics Problem which I am not to sure where to start it from. The problem is: A real inverted image I of an object O is formed by a certain lens. The object-image speration is d = 0.40m, measured along the central axis of the lens. The image is just half the size of the...- dlaszlo88
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- Image Lens Physics Separation
- Replies: 3
- Forum: Introductory Physics Homework Help
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How Does Focal Length Affect the Focus Point of a Lens?
Hi .I am reall y confused about the focal length of lens.i understand that it is the length from the lens to the point where parallel beams coming from infinity after passing through the lens cross one each other.My question ,knowing thew focal length wher exactly does it help?does it have any... -
Stargazing Upgrading Telescope Lens: Is it Possible for Meade StarQuest 60AZ-M?
IS it possible for this one? I was given an older Meade telescope today the specs: StarQuest Model: 60AZ-M 60mm (2.4") Altazimuth refratcing telescope Lens specs: - 5x24mm viewfinder - SR4mm H12.5mm and H25mm eyepieces (0.965" barrel diameter) - 2x Barlow lenses What can i...- vincentm
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- Lens Telescope
- Replies: 22
- Forum: Astronomy and Astrophysics
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Help Solve Physics Problem Involving a Convex Lens
Lez prob hi, An object is moving with velocity 0.01 m/s towards a convex lens of focal length 0.3m. Find the magnitude of rate of separation of image from the lens when the object is at a distance of 0.4 m from the lens. Also calculate the magnitude of the rate of change of the lateral...- navisangha
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- Convex Convex lens Lens Physics
- Replies: 2
- Forum: Introductory Physics Homework Help
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Photographing a Bird: Solve for Camera Lens Focus
Hi! I am having trouble with this question: You are trying to photograph a bird sitting on a tree branch, but a tall hedge is blocking your view. However, as the drawing shows, a plane mirror reflects light from the bird into your camera. If x = 4.3 m and y = 4.5 m in the drawing, for what...- osustudent2010
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- Bird Camera Focus Lens
- Replies: 18
- Forum: Introductory Physics Homework Help
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Solution to Optics Lens Problem: Image Distance in f
i need help! Given: A real object is located to the left of a convergent lens. The object's distance from the lens is 7/3f and its focal length is f. What is the image distance in terms of f? I tried the formula 1/f = 1/di + 1/do... it didn't work- Gshan12
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- Lens Optics
- Replies: 4
- Forum: Introductory Physics Homework Help
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Experimenting with a Diverging Lens: Discovering the Focal Point
Hey all, I recently did an experiment using a diverging or convex lens, to produce different images according to the focal point. For the experiment I found the focal length, and set up the lens and light source at that distance. I used just paper for a screen to produce the real images created...- SwAnK
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- Focal Lens Point
- Replies: 4
- Forum: Introductory Physics Homework Help
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What Happens to Photons in a System of Lenses Designed for Permanent Refraction?
If you could set up a system of lenses so that once a steady light stream enters the system, it will be refracted within the same system permanently, what will happen to the photons? Would it take an infinite number of lenses to get the exact refraction? -
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Show Two Positions of Converging Lens for Sharp Image Formation
A bright object is placed on one sid eof a converging lens of focal length f, and a white screen for viewing the image is on the opposite side. The distance d_T = d_i + d_0 between the object and the screen is kept fixed, but the lens can be moved. Show that if d_t > 4f , there will be two...- leolaw
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- Converging Lens
- Replies: 8
- Forum: Introductory Physics Homework Help