Introduction:
Just as reflection takes places at curved and plane surfaces, similarly, refraction can also occur at plane and curved surfaces. In the last unit, we have discussed about the refraction through a prism. In this unit we shall look at refraction at curved surfaces. Figure given above shows refraction at a curved surface.
Image Formed by Refraction at a Curved Surface:
In Figure given above, point O is the object near the convex spherical refracting surface of radius of curvature r. Surface separates two media whose indices of refraction differ, that of medium in which incident light falls on surface being m1 and that on the other side of the surface being m2.
The light source ray which enters normally at point P would pass through undeviated and pass through center of curvature. The bright ray which enters at any other angle (Q for instance) would be deviated or converged to intersect with the ray which passing through center of curvature to create the real image. If surface were concave then refracting ray would diverge and if created backwards would form the virtual image as shown in figure (b)
The object and image distance are related by the formula (here we have written only the result. The formula is not derived.)
μ1/u + μ2/v = μ2 - μ1/r................Eq.1
Where
u = object distance
v = image distance
r = radius pf curvature of surface
μ1, μ2 = refractive index of the two media
Note that m1, is refractive index of the medium in which the light is initially traveling before it gets in medium with refractive index m2.
We should use sign conventions if we are to use equation to the variety of cases. Side of surface in which light rays originate stated as front side. Other side is known as back side. Real images are formed by refraction in back of surface in contrast with mirrors, where real images are formed in front of reflecting surface. Due to difference in location of real images, refraction sign conventions for v and r are opposite reflection sign conventions. Just as in refraction image formed can be enlarged or diminished and magnification of image is provided by
m = (μ1/μ2)(v/u)
Refraction through Lenses:
Phenomenon of refraction is change in direction of the ray of light when it travels from one medium to another of different density.
Refraction through lenses involves same change in direction of light rays.
The lens is the portion of the transparent medium bounded by two spherical surfaces or by the plane and the spherical surface. The different kinds of lenses are given.
Usually, a converging or convex lens makes rays of light originating from the point come together at another point while diverging or concave lens makes rays of light that pass through the point spread out or diverge.
Major characteristics of the Lens:
The typical lens of whatever kind has major characteristics
i) The Principal Axis: This is line joining the centers of curvature of two curved surfaces forming lens.
ii) Optical Centre: For every lens there is point C through which rays of light pass through without being deviated by lens. This point is known as optical center of the.
iii) The Principal Focus: The principal focus F of the converging lens is point to which all rays parallel and close to principal axis converge after refraction through lens. Principal focus of the diverging lens is point from which all rays parallel and close to principal axis seems to diverge from after refraction through lens.
iv) Focal Length: Focal length F is distance between optical center and principal focal of the lens. Principal focus of the converging lens is on far side from the incident rays while for the diverging lens the principal focus is on same side as the incident rays and the refracted rays don't really pass through it.
Tutorsglobe: A way to secure high grade in your curriculum (Online Tutoring)
Expand your confidence, grow study skills and improve your grades.
Since 2009, Tutorsglobe has proactively helped millions of students to get better grades in school, college or university and score well in competitive tests with live, one-on-one online tutoring.
Using an advanced developed tutoring system providing little or no wait time, the students are connected on-demand with a tutor at www.tutorsglobe.com. Students work one-on-one, in real-time with a tutor, communicating and studying using a virtual whiteboard technology. Scientific and mathematical notation, symbols, geometric figures, graphing and freehand drawing can be rendered quickly and easily in the advanced whiteboard.
Free to know our price and packages for online physics tutoring. Chat with us or submit request at [email protected]
the annealed copper conductors generally in round shape are employed for winding small and medium capacity electrical machines.
tutorsglobe.com seepage pit-construction assignment help-homework help by online rain water harvesting tutors
direct-current circuits and instruments tutorial all along with the key concepts of resistors in series and in parallel, kirchhoff's rules, ammeters and voltmeters, shunts and multipliers, wheatstone bridge, meter bridge and potentiometer
global weather and climatic patterns tutorial all along with the key concepts of components of the earth, energy cycle, terrestrial atmosphere, weather and landform, greenhouse effect, ozone layer depletion, environmental management, environmental modeling, environmental cost-benefit analysis
reversible, irreversible and cyclic process tutorial all along with the key concepts of the carnot cycle, isothermal expansion, adiabatic expansion, isothermal compression, adiabatic compression, and total work done on the system
homologous series-functional groups and isomerism tutorial all along with the key concepts of organic compounds by functional groups, structural isomerism, geometric isomerism
tutorsglobe.com osmosis assignment help-homework help by online cell membrane tutors
www.tutorsglobe.com offers answering questions to various causes of inflation, demand-pull inflation, structuralist approach, cost-push inflation, theory and concepts of inflation, economics assignment help and homework help.
Applications of Filters tutorial all along with the key concepts of Audio frequency uses of filters, Bandpass filters at radio frequencies, EMI and transient suppressor filters, Spectrum sweeping
Paramecium tutorial all along with the key concepts of Physical Appearance of paramecium, paramecium Feeding, Respiration process in Paramecium, Movement in Paramecium, Reproduction and Importance of paramecium
There is broad agreement that financial reporting standards have enhanced the quality of financial statements. However, we should be aware to the potential problems related with their use.
Alpine and Aquatic Biomes tutorial all along with the key concepts of Alpine Biomes, Freshwater Biomes, Ocean or Marine Biomes, Marine Rocky Shore, Marine Sandy Beach, Mangrove Swamp, Coral Reef, Continental Shelf
tutorsglobe.com reduction assignment help-homework help by online dark reactions tutors
Gene interactions tutorial all along with the key concepts of Characteristics of X-linked Traits, The Modern view of the Gene, Codominant alleles, Incomplete dominance, Genes and Chromosomes
online sat exam preparation course and online sat tutoring package offered by TutorsGlobe are the most comprehensive and customized collection of study resources on the web, offering best collection of sat practice papers, quizzes, sat test papers, and guidance.
1964702
Questions Asked
3689
Tutors
1476487
Questions Answered
Start Excelling in your courses, Ask an Expert and get answers for your homework and assignments!!