Sci10 Simplified Optics, Lens Mirrors, Refraction, Reflection PDF

1 CDADeLeon_Sci10_Mirrors and Lenses  Reflection Reflection is the property of light which refers to the bouncing back of light rays CDADeLeon_Sci10_Light 2 Reflection CDADeLeon_Sci10_Light 3  Reflection Incident Rays – the ray of light approaching...

1 CDADeLeon_Sci10_Mirrors and Lenses  Reflection Reflection is the property of light which refers to the bouncing back of light rays CDADeLeon_Sci10_Light 2 Reflection CDADeLeon_Sci10_Light 3  Reflection Incident Rays – the ray of light approaching the mirror Reflected Rays – The ray of light which leaves the mirror CDADeLeon_Sci10_Light 4  Incident Anything falling or striking on something CDADeLeon_Sci10_Mirrors and Lenses 5  Ray A line with an endpoint extending in one direction CDADeLeon_Sci10_Mirrors and Lenses 6  Angle A figure between two rays CDADeLeon_Sci10_Mirrors and Lenses 7  Law A statement of fact CDADeLeon_Sci10_Mirrors and Lenses 8  Check Point! What do you call the ray that strikes the mirror surface? How about the ray that bounces off the mirror? CDADeLeon_Sci10_Mirrors and Lenses 9  ANSWER Incident and reflected rays CDADeLeon_Sci10_Mirrors and Lenses 10  Check Point! How will you compare the angle between the normal line and the incident ray to the angle between the normal line and the reflected ray? CDADeLeon_Sci10_Mirrors and Lenses 11  ANSWER The angles have the same value CDADeLeon_Sci10_Mirrors and Lenses 12  Check point! What happened when a light strikes to the mirror? CDADeLeon_Sci10_Mirrors and Lenses 13 ANSWER It bounces back CDADeLeon_Sci10_Mirrors and Lenses 14 Law of Reflection The angle of incidence is equal to the angle of reflection i =  r CDADeLeon_Sci10_Mirrors and Lenses 15 SAMPLE PROBLEM What is the angle of reflection? CDADeLeon_Sci10_Mirrors and Lenses 16 SAMPLE PROBLEM What is the angle of reflection at mirror 2? CDADeLeon_Sci10_Mirrors and Lenses 17 Sample Problem The angle between the of incidence and reflected ray is 40o a. What is the angle of reflection? 20o CDADeLeon_Sci10_Light 18 Sample Problem The angle between the of incidence and reflected ray is 40o b. The angle of incidence is increased by 5o. What is the angle of reflection? 25o CDADeLeon_Sci10_Light 19 Sample Problem The angle between the of incidence and reflected ray is 40o c. The angle of incidence is decreased by 4o. What is the angle of reflection? 16o CDADeLeon_Sci10_Light 20 SAMPLE PROBLEM What is the angle of reflection? CDADeLeon_Sci10_Light 21 Multiple Reflection Multiple images are produced when two mirrors are arranged at a certain angle  360  N =  −1    CDADeLeon_Sci10_Mirrors and Lenses 22 Multiple Reflection N = number of images formed = angle between the mirrors  360  N =  −1    CDADeLeon_Sci10_Mirrors and Lenses 23 GUIDE QUESTIONS 1. What happens to the number of images formed as you vary the angle between the mirrors? 2. What relationship can you see between the images formed and angle? CDADeLeon_Sci10_Mirrors and Lenses 24 Multiple Reflection Parallel mirrors on the other hand produce infinite number of images. CDADeLeon_Sci10_Mirrors and Lenses 25  Optics Study of light Geometric Optics Deals with image formation CDADeLeon_Sci10_Mirrors and Lenses 26  Mirror Any object that has a smooth, reflecting surface Plane Mirror Spherical Mirror Mirror that has a flat Mirror that has a curved surface surface CDADeLeon_Sci10_Mirrors and Lenses 27 CDADeLeon_Sci10_Mirrors and Lenses 28 CDADeLeon_Sci10_Mirrors and Lenses 29 Image Formation L.O.S.T. L Location O Orientation S Size T Type CDADeLeon_Sci10_Mirrors and Lenses 30 Location Where the image is found 1. In front of the mirror 2. In behind of the mirror CDADeLeon_Sci10_Mirrors and Lenses 31  Orientation How is it positioned? 1. Laterally Reversed – left becomes right 2. Erect – upright 3. Inverted – head becomes foot CDADeLeon_Sci10_Mirrors and Lenses 32  Size How big or small? 1. Enlarged– increase in size 2. Reduced – decrease in size 3. Same Size CDADeLeon_Sci10_Mirrors and Lenses 33  Type The nature of the image formed 1. Real – inverted; formed in front of the mirror 2. Virtual – erect; formed behind the mirror CDADeLeon_Sci10_Mirrors and Lenses 34 Image Formation Plane Mirror L Behind the mirror O Erect and Laterally Reversed S Same Size T Virtual CDADeLeon_Sci10_Mirrors and Lenses 35 CDADeLeon_Sci10_Mirrors and Lenses 36 Object Distance (do) distance from object to mirror Image Distance (di) distance from mirror to image CDADeLeon_Sci10_Mirrors and Lenses 37 Lateral Magnification the ratio of image height (y’) to object height (y) y' di M = =− y do CDADeLeon_Sci10_Mirrors and Lenses 38 Lateral Magnification If M is: (+) virtual image and upright (-) real image and inverted CDADeLeon_Sci10_Mirrors and Lenses 39 Convex Mirror Concave Mirror curves inward in the bulges outward to the direction of the incident incident rays rays CDADeLeon_Sci10_Mirrors and Lenses 40  Guide Questions How will you describe the image in a plane mirror? Provide the L.O.S.T. CDADeLeon_Sci10_Mirrors and Lenses 41 Image Formation Plane Mirror L Behind the mirror O Erect and Laterally Reversed S Same Size T Virtual CDADeLeon_Sci10_Mirrors and Lenses 42 Image Formation Plane Mirror L Behind the mirror O Erect and Laterally Reversed S Same Size T Virtual CDADeLeon_Sci10_Mirrors and Lenses 43 CDADeLeon_Sci10_Mirrors and Lenses 44 CDADeLeon_Sci10_Mirrors and Lenses 45  46 CDADeLeon_Sci10_Mirrors and Lenses 47 CDADeLeon_Sci10_Mirrors and Lenses Spherical Mirror Terminologies Center of Curvature (C) – The center of the sphere where the mirror was taken Vertex (V) – The center of the mirror CDADeLeon_Sci10_Mirrors and Lenses 48 Spherical Mirror Terminologies Radius of Curvature (R) – radius of the sphere; distance between C and V CDADeLeon_Sci10_Mirrors and Lenses 49 Spherical Mirror Terminologies Principal Axis – the straight line joining C and V Principal Focus (F) – the focal point where reflected rays meet CDADeLeon_Sci10_Mirrors and Lenses 50 Spherical Mirror Terminologies Focal length (f) – distance between the vocal point and the vertex 𝑅 𝑓= 2 CDADeLeon_Sci10_Mirrors and Lenses 51  Ray Diagrams in Mirrors Parallel from Principal Axis to Focal Point (P-F) ray C F P P F C In a concave mirror a ray of light parallel to In a convex mirror a ray of light parallel to the the principal axis after reflection passes principal axis after reflection appears to through the focus. diverge from the focus. CDADeLeon_Sci10_Mirrors and Lenses 52  Ray Diagrams in Mirrors Focal Point to Parallel from Principal Axis (F-P) ray C F P P F C In a concave mirror a ray of light passing In a convex mirror a ray of light directed through the focus after reflection goes towards the focus after reflection goes CDADeLeon_Sci10_Mirrors and Lenses 53 parallel to the principal axis. parallel to the principal axis.  Ray Diagrams in Mirrors Center of Curvature (C-C) ray C F P P F C In a concave mirror a ray of light passing In a convex mirror a ray of light directed through the center of curvature after towards the center of curvature after reflection is reflected back along the same reflection is reflected back along the same direction. direction. CDADeLeon_Sci10_Mirrors and Lenses 54 Ray 1 C F P P to F P F C Ray 2 F to P C F P P F C Ray 3 C F P C to C CDADeLeon_Sci10_Mirrors and Lenses P F C 55 Location of L ocation O rientation S ize T ype the Object (In front; behind the (Upright; inverted) (Enlarged; reduced; (Real or Virtual) mirror) same size) CONCAVE MIRROR A. Beyond C B. At the C C. Between C and F D. At F E. Between F and V CONVEX MIRROR F. Beyond C in front of the mirror G. Between F & V in front of the mirror CDADeLeon_Sci10_Mirrors and Lenses 56 CONCAVE – Beyond C Between C and L F; in front C F V O Inverted S Reduced CDADeLeon_Sci10_Mirrors and Lenses T Real 57  CONCAVE – At C L At C; in front O Inverted P C F V S Same size CDADeLeon_Sci10_Mirrors and Lenses T Real 58  CONCAVE – Between C and F L Beyond C; in front P C F V O Inverted S Enlarged CDADeLeon_Sci10_Mirrors and Lenses T Real 59 CONCAVE – At F L At infinity O Inverted C F V S Highly enlarged CDADeLeon_Sci10_Mirrors and Lenses T Real 60 CONCAVE – Between F and V Behind the L mirror O Upright C F V S Highly enlarged CDADeLeon_Sci10_Mirrors and Lenses T Virtual 61 CONCAVE – At Infinity L At the Focus (F) O Inverted C F V S Highly reduced CDADeLeon_Sci10_Mirrors and Lenses T Real 62  CONVEX Behind the L mirror O Upright V F C S Reduced CDADeLeon_Sci10_Mirrors and Lenses T Virtual 63 64 CDADeLeon_Sci10_Mirrors and Lenses  Lens Uses refraction to produce a real or virtual image a lens thicker at the middle; a Convex Lens converging lens a lens thicker at the edges; a Concave Lens diverging lens CDADeLeon_Sci10_Mirrors and Lenses 65 Convex Lens Concave Lens CDADeLeon_Sci10_Mirrors and Lenses 66 Convex Lens Concave Lens CDADeLeon_Sci10_Mirrors and Lenses 67 68 CDADeLeon_Sci10_Mirrors and Lenses  Lenses Terminologies Focal Points (F1 and F2) – the principal focus of the lens a. Near Focal Point – is the focus F on the same side of the lens as the incident light. b. Far Focal Point – is the focus F on the opposite side to the incident light. CDADeLeon_Sci10_Mirrors and Lenses 69 Lenses Terminologies Optical Center (O) – where all light rays pass through without being bent Principal Axis (P) – the line joining the optical center to the focal points CDADeLeon_Sci10_Mirrors and Lenses 70 Lenses Terminologies Focal length (f) – distance from O to F1 or F2 Centers of Curvatures (2F1 and 2F2) – centers of the arcs forming the sides of the lengths CDADeLeon_Sci10_Mirrors and Lenses 71  Ray Diagrams in Lenses Parallel from Principal Axis to Focal Point (P-F) ray 2F1 F1 O F2 2F2 2F1 F1 O F2 2F2 In a convex lens a ray of light parallel to the In a concave lens it appears to diverge from principal axis after refraction passes through the focus on the same side of the lens. the focus on the other side of the lens. CDADeLeon_Sci10_Mirrors and Lenses  Ray Diagrams in Lenses Focal Point to Parallel from Principal Axis (F-P) ray 2F1 F1 O F2 2F2 2F1 F1 O F2 2F2 In a convex lens a ray of light passing In a concave lens a ray of light directed through the focus after refraction goes towards the focus after refraction goes parallel to the principal axis. parallel to the principal axis. CDADeLeon_Sci10_Mirrors and Lenses  Ray Diagrams in Lenses Optical Center (O) ray 2F1 F1 O F2 2F2 2F1 F1 O F2 2F2 In a convex lens and concave lens a ray of light passing through the optical center goes without any deviation. CDADeLeon_Sci10_Mirrors and Lenses 74 Ray 1 P to F 2F1 F1 O F2 2F2 2F1 F1 O F2 2F2 Ray 2 F to P 2F1 F1 O F2 2F2 2F1 F1 O F2 2F2 Ray 3 O ray 2F1 F1 O F2 2F2 2F1 F1 O F2 2F2 CDADeLeon_Sci10_Mirrors and Lenses 75  Location of L ocation O rientation S ize T ype the Object (In front; behind the (Upright; inverted) (Enlarged; reduced; (Real or Virtual) lens) same size) CONVEX LENS A. Beyond 2F1 B. At 2F1 C. Between 2F1 and F1 D. At F1 E. Between F1 and O CONCAVE LENS F. At 2F2 G. At F2 H. Between F2 and O CDADeLeon_Sci10_Mirrors and Lenses 76  CONVEX – Beyond 2F1 L In front 2F1 F1 O F2 2F2 O Inverted S Reduced CDADeLeon_Sci10_Mirrors and Lenses T Real 77  Location of L ocation O rientation S ize T ype the Object (In front; behind the (Upright; inverted) (Enlarged; reduced; (Real or Virtual) lens) same size) CONVEX LENS A. Beyond 2F1 B. At 2F1 C. Between 2F1 and F1 D. At F1 E. Between F1 and O CONCAVE LENS F. At 2F2 G. At F2 H. Between F2 and O CDADeLeon_Sci10_Mirrors and Lenses 78  CONVEX – At 2F1 L In front 2F1 F1 O F2 2F2 O Inverted S Same size CDADeLeon_Sci10_Mirrors and Lenses T Real 79 CONVEX – Between 2F1 and F1 L In front 2F1 F1 O F2 2F2 O Inverted S Enlarged CDADeLeon_Sci10_Mirrors and Lenses T Real 80  CONVEX – At F1 L At infinity; 2F1 F1 O F2 2F2 O enlarged = S No image is formed CDADeLeon_Sci10_Mirrors and Lenses T 81  CONVEX – Between F1 and O L Behind O Upright/Erect 2F1 F1 O F2 2F2 S Enlarged CDADeLeon_Sci10_Mirrors and Lenses T Virtual 82  CONCAVE L Behind O Upright FI O S Reduced CDADeLeon_Sci10_Mirrors and Lenses T Virtual 83  Summary A converging lens forms either a real or a virtual image. A diverging lens always forms a virtual image. CDADeLeon_Sci10_Mirrors and Lenses 84  85 CDADeLeon_Sci10_Mirrors and Lenses Optical Instrument Any arrangement which makes use of a combination of lenses, mirrors or prisms, is called an optical instrument. CDADeLeon_Sci10_Mirrors and Lenses 86 Human Eye Light enters through the transparent covering, the cornea. The amount of light that enters is regulated by the iris, the colored part of the eye that surrounds the pupil. CDADeLeon_Sci10_Mirrors and Lenses 87 Human Eye The pupil is the opening through which light passes. Light passes through the pupil and lens and is focused on a layer of tissue at the back of the eye—the retina. CDADeLeon_Sci10_Mirrors and Lenses 88 Human Eye The fovea is a small region in the center of our field of view where we have the most distinct vision. The blind spot is where all the nerve carrying the information leaves the eye CDADeLeon_Sci10_Mirrors and Lenses 89 Human Eye CDADeLeon_Sci10_Mirrors and Lenses 90  Human Eye Defects With normal vision, your eye can accommodate to clearly see objects from infinity (the far point) down to 25 cm (the near point). Common eye vision defects include the following: a. Hyperopia b. Myopia c. Astigmatism CDADeLeon_Sci10_Mirrors and Lenses 91  Myopia/Nearsightedness Nearby objects are clearer than farther objects Can be corrected by a diverging lens CDADeLeon_Sci10_Mirrors and Lenses 92 Hyperopia/Farsightedness Farther objects are clearer than nearer objects Can be corrected by a converging lens CDADeLeon_Sci10_Mirrors and Lenses 93 Astigmatism Results when the cornea is curved more in one direction than the other. Corrected by a cylindrical lens CDADeLeon_Sci10_Mirrors and Lenses 94 Camera 1. Aperture – allows light to enter camera 2. Convex lens – refracts light rays 3. Shutter – controls the amount of light that enters CDADeLeon_Sci10_Mirrors and Lenses 95 Camera 4. Diaphragm – changes the size of the aperture 5. Film – the screen where the image is formed CDADeLeon_Sci10_Mirrors and Lenses 96 Camera CDADeLeon_Sci10_Mirrors and Lenses 97 Human Eye vs. Camera FUNCTIONS EYE CAMERA Opening for entry of light Pupil Aperture Regulation of size opening Iris Diaphragm Cornea, lens. Vitreous and Refracting system Biconvex lens aqueous humor Where image is formed Retina Film/Digital Sensory Array Regulation of time Eyelid Shutter exposure to light Ciliary muscles changing Adjustment in lens to film Focusing mechanism the shape of the lens distance CDADeLeon_Sci10_Mirrors and Lenses 98  Magnifying Lens Uses a single converging lens to create an enlarged, upright, and virtual image CDADeLeon_Sci10_Mirrors and Lenses 99  Microscope A compound microscope uses two converging lenses of short focal length. The objective lens produces a real image of a close object. CDADeLeon_Sci10_Mirrors and Lenses 100  Microscope The image is farther from the lens than the object so it is enlarged. The eyepiece forms a virtual image of the first image, further enlarged. CDADeLeon_Sci10_Mirrors and Lenses 101  Telescopes Used for viewing distant objects (e.g. Celestial bodies) It has two types (Reflecting and Refracting) CDADeLeon_Sci10_Mirrors and Lenses 102 CDADeLeon_Sci10_Mirrors and Lenses 103  Reflecting Refracting Telescopes Telescopes Uses mirrors Uses lenses CDADeLeon_Sci10_Mirrors and Lenses 104 Binoculars Each side of a pair of binoculars uses a pair of prisms that flips the image right-side up. CDADeLeon_Sci10_Mirrors and Lenses 105  106 CDADeLeon_Sci10_Mirrors and Lenses GUIDE QUESTIONS 1. Which among the glass and air has the greatest density? 2. What happens to the light as it travels from the air to glass? 3. How does the angle of refraction compare to the angle of incidence in each angle? CDADeLeon_Sci10_Mirrors and Lenses 107 Refraction Refraction refers to the bending of light rays as it passes from one medium to another CDADeLeon_Sci10_Mirrors and Lenses 108  Index of Refraction MATERIAL n MATERIAL n SOLIDS LIQUIDS (20oC) Ice 1.309 Methanol 1.329 Fluorite 1.434 Water 1.333 Polystyrene 1.49 Ethanol 1.36 Rock salt 1.544 Carbon 1.460 Tetrachloride Quartz 1.544 Turpentine 1.472 Diamond 2.417 Glycine 1.473 GLASSES GASES Crown 1.52 Air at STP 1.0003 Vacuum CDADeLeon_Sci10_Mirrors and Lenses 1.000 109  Refraction SLOWER Less Dense to Denser → TOWARDS the normal CDADeLeon_Sci10_Light 110  Refraction FASTER Denser to Less Dense → AWAY from the normal CDADeLeon_Sci10_Light 111  Where should you aim the target? ABOVE or BELOW the fish? CDADeLeon_Sci10_Light 112 Refraction BELOW the fish → Light travels from less dense (air) to denser (water); the light rays travels towards the normal CDADeLeon_Sci10_Light 113 Index of Refraction c n = refractive index n= c = speed of light v = new velocity of v light CDADeLeon_Sci10_Mirrors and Lenses 114  Mirage The refraction in air due to the differences in temperature of air and surface CDADeLeon_Sci10_Light 115 Snell’s Law The incident and refracted rays, and the normal to the surface all lie in the same plane CDADeLeon_Sci10_Mirrors and Lenses 116 Diffraction Bending of light as it passes through an edge Example: passing of light through a slit CDADeLeon_Sci10_Light 117 Diffraction CDADeLeon_Sci10_Light 118  Diffraction and shadows Like sound and water waves, light shows interference, diffraction and polarization. Diffraction occurs when a wave passes through an opening not too much wider than the wavelength of the wave. Observing diffraction with light is evidence that light is a wave. Diffraction and shadows You can see diffraction in a shadow cast by a sharp edge with light from a laser. The edge of the shadow has ripples in it. The ripples are caused by diffraction. Young’s double slit experiment In 1807, Thomas Young proved light was a wave when he showed that two beams of light could interfere with each other. Interference When two waves meets, they have an effect with each other CDADeLeon_Sci10_Light 122 Interference CDADeLeon_Sci10_Light 123  Light is a wave The bright bands in an interference pattern are where the light waves from both slits are in phase at the screen (constructive interference). The dark bands appear where the light waves reach the screen out of phase (destructive interference). Optical Density Give the degree of transparency of a material CDADeLeon_Sci10_Light 125 Optical “Ether” The medium where light travels according to the Wave Theory CDADeLeon_Sci10_Light 126 CDADeLeon_Sci10_Light 127 Diffraction gratings A diffraction grating actually a series of thin parallel grooves on a piece of glass or plastic. When light goes through a diffraction grating, each groove scatters the light so the grating acts like many parallel slits. Spectrometers A spectrometer is a calibrated diffraction grating used to create a spectrum. The spectrometer has a scale that allows you to read different wavelengths of light directly from the pattern of light made by the grating. Polarization The orientation of light is called its polarization. Only transverse waves can have polarization.  Polarizers A polarizer is a material that allows light of only one polarization to pass through it. Light with a single polarization is called polarized light.  Applications of polarization Polarized sunglasses reduce glare because they selectively absorb light with horizontal polarization while letting other light through. Applications of polarization Images on a LCD (liquid crystal display)are made using polarized light. Each liquid crystal window can be electronically controlled to act like a polarizer, or not.  The Particle Nature of Light: Phosphorescence Key Question: How does light fit into the atomic theory of matter? Objectives: ◼ Explore the quantum theory of light. ◼ Experiment with a photoluminescent material Energy, color and light The lowest-energy photons we can see are the ones that appear red to our eyes. White light is a mixture of photons with a range of energy.  The intensity of light is Energy and intensity of light a combination of both the number of photons and the energy per photon. To make a red light with an intensity of 100 W/m2 takes a lot more photons than it does to make the same intensity with blue light. Energy and intensity of light If glow-in-the-dark plastic is exposed to light, it stores some energy and releases the energy later by giving off light. The process of Glow-in-the-dark plastic releasing stored light demonstrates that a single energy is called atom only absorbs a photoluminescence. single photon at a time. Light and atoms Almost all atoms absorb and emit light. For most atoms, the absorption and emission of light happens in less than one-millionth of a second.  How 3-D Movies Work Cinematographers, ophthalmologists, optical engineers, and computer graphic designers all play a role in the development of modern 3-D movie technology. To create the illusion of three- dimensions on a flat screen, each eye must receive its own separate image of the movie, from a slightly different perspective, mimicking the way your eyes take in a real three-dimensional scene.