Duncanrig Secondary School East Kilbride S2 Physics Elective Light and Sound Name: Pupil Booklet Class: SCN 3-11a - By exploring the refraction of light when passed through different materials, lenses and prisms, I can explain how light can be used in a variety of applications. SCN 4-11a By recording and analysing sound signals, I can describe how they can be manipulated and used in sound engineering. Learning Outcomes Homework Exercises Unit Summary
S2 Physics Elective Light and Sound Learning Outcomes How Confident am I with the Learning Outcomes? Circle the faces to keep a record of your progress. I am confident that I understand this and I can apply this to problems I have some understanding but I need to revise this some more I don t know this or I need help because I don t understand it You can use this to help you pick the areas of the unit that need the most revision. As you revise your class work you will be able to circle more and more smiley faces. If that does not help then you should ask your teacher! Learning Outcomes 1. State that the speed of light in air/vacuum is 300 000 000 m/s. 2. State that light slows down as it passes from air/vacuum into another transparent material. 3. State that refraction is the change in speed of light as it travels from one medium to another. 4. State that refraction causes the light to change direction, if the incident angle is not 90, as it passes from medium to medium. 5. State that the normal (an imaginary line) is drawn at 90 to the boundary where the ray strikes. Can you do this? Comments Page 1
S2 Physics Elective Light and Sound Learning Outcomes 6. State that all angles are measured from the normal. 7. Be able to measure angles from the normal. 8. State that the incident angle is less than the refraction angle for light travelling from Perspex to air. 9. Recognise the path a ray of light will follow through different transparent shapes. 10. Be able to use appropriate words to describe an image formed by a convex lens: Magnified Diminished Upright Inverted Real Virtual Laterally Inverted 11. Draw/describe the shape of a convex lens side on. 12. Be able to identify some applications of convex lenses. 13. State that the focal length can be measured from the centre of the lens to the focal point. 14. Describe how to measure the principal focal length of a convex lens. Page 2 15. Identify on a diagram the following ten main parts of the eye: Cornea
S2 Physics Elective Light and Sound Learning Outcomes Pupil Ciliary muscles Lens Iris Retina Optic nerve Eye Muscles Blind Spot Fovea (yellow spot) 16. State the function of the following parts of the eye: Cornea Pupil Ciliary muscles Lens Iris Retina Optic nerve Eye Muscles Fovea (yellow spot) 17. State the meaning of the word transparent and name materials that are transparent. 18. State that the ability of the eye lens to change shape in order to focus on objects at different distances is called accommodation. 19. Draw/describe a thin/thick convex lens. 20. State that the eye lens is thinner when objects are distant but thicker when objects are near to produce a focused Page 3
S2 Physics Elective Light and Sound Learning Outcomes image on the retina. 21. State that two eye defects are short sighted and long sighted. 22. State that people who are longsighted see a blurry image when looking at objects nearby. 23. State that people who are short-sighted see a blurry image when looking at objects far away. 24. State that light from distant objects appears parallel. 25. State that light from nearby objects appears diverging. 26. Draw/describe the shape of a concave lens. 27. Draw/describe the effect of convex/concave lenses on parallel rays of light. 28. State that a convex lens can correct long-sightedness and a concave lens can correct short-sightedness. 29. State that the pupil size is dependent on light levels. Larger in dim light and smaller in bright light. 30. State that the blind spot is where the optic nerve leaves the retina. 31. Explain why no light is detected if it lands on the blind spot. 32. Carry out a simple experiment to show Page 4
S2 Physics Elective Light and Sound Learning Outcomes that your own eye has a blind spot. 33. State that an optical illusion is a false or deceptive visual image. 34. State that the image produced by a pinhole camera is upside down and reversed. 35. State that increasing the size of the pinhole make the image brighter but less sharp. 36. State that a convex lens can be used to make the image produced by pinhole camera sharper. 37. Form a sharp image of an object on the screen of a pinhole camera. 38. Explain that the pinhole camera and the human eye form an image in the same way. 39. State that the image formed on the retina of the eye is upside side-down and reversed. 40. State that the three main parts of a refracting telescope are the light tight tube, objective lens and eyepiece lens. 41. Describe how to measure the principal focal length of a convex lens. 42. State that the magnification of a refracting telescope can be calculated from the formula: magnification = focal length of objective lens / focal length of eyepiece lens Page 5
S2 Physics Elective Light and Sound Learning Outcomes 43. State that the objective lens is designed to collect light from distant objects. 44. State the eyepiece lens is designed to magnify the image produced by the objective lens. 45. State the image produced by the objective lens will be brighter is the diameter of the lens is increased. 46. Identify on a diagram the following 8 parts of the ear. outer ear small bones outer lobe semicircular canals ear canal cochlea ear drum nerve to the brain 47. Describe the function (what it does) of the five main parts of the ear. Page 6 48. State that sound is caused by vibrations 49. State that frequency is the number of vibrations per second. 50. State that the higher the frequency of the vibrations the higher the pitch (and vice versa). 51. State that the human ear cannot detect sounds of a very high pitch. 52. State and explain why sound travels more easily in solids than in liquids and gases.
S2 Physics Elective Light and Sound Learning Outcomes 53. Explain, by use of a diagram, the effect of varying (changing) the loudness of a sound as seen on an oscilloscope. 54. Explain, by use of a diagram, the effect of varying (changing) the frequency of a sound as seen on an oscilloscope. 55. State that plucking a string harder increases the amplitude of the sound from a stretched string. 56. State that shortening a stretched string and tightening a stretched string both increase the frequency of the sound produced when the string is plucked. 57. Be able to record sound using Audacity. 58. Be able to manipulate recorded sound using Audacity. Page 7
Where appropriate answer the questions in this homework in full sentences in the spaces provided. Light and Sound Homework 1 Refraction 1. What is the speed of light in air/vacuum? 2. What is the definition of refraction? 3. What word means that light can pass through? 4. What imaginary line should all angles be measured from? 5. When light passes from Perspex into air how does the incident angle compare with the refraction angle? (smaller or larger?) 6. Match the words with their meanings. Use a ruler. Words Diminished Virtual Inverted Laterally Inverted Magnified Real Upright Meanings Increased in size Decreased in size Image is the same way up as the object Image is upside down compared to the object Image can be projected into a screen Image cannot be projected onto a screen, can only be seen by the eye. Flipped horizontally. Page 8
Where appropriate answer the questions in this homework in full sentences in the spaces provided. Light and Sound Homework 2 The Eye 1. Name the 10 parts of the human eye. 2. In the box, draw the shape of a convex and concave lens (as viewed side on). Include labels. 3. What shape is the lens (thick or thin) when looking at a nearby object? 4. Maria looks at a beautiful lake far in the distance. She then turns to look at her friend Kerry, standing beside her and explains if it were not for physics, I would not understand how I see this wonderful view. a. Describe the shape of the lens in Maria s eye upon viewing the distant lake. b. Describe the change to her eye lens when looking at Kerry close up. c. Name the process that allows the thickness of eye lens to change according to the object s distance. 5. If you looked at the print of this homework exercise with a convex lens close up, what would it look like? Page 9
Where appropriate answer the questions in this homework in full sentences in the spaces provided. 6. What happens to the pupil of your eye in a. Dim light? b. Bright light? 7. a. Describe the position of the blind spot in the eye. b. Why is it called the blind spot? 8. The mysterious floating finger is an example of an optical illusion. What does the term optical illusion mean? 9. Describe the function of the following parts of the eye: Iris: Cornea: Retina: 10. Name two eye defects and state which type of lens can be used to correct each of them. Page 10
Where appropriate answer the questions in this homework in full sentences in the spaces provided. Light and Sound Homework 3 The Pinhole Camera and Refracting Telescope 1. Complete the table with the parts of the pinhole camera that correspond to the parts of the eye. Parts of the eye Pupil Lens Retina Parts of the Pinhole Camera 2. Describe the image formed on the screen of a pinhole camera when looking at an object. 3. The image on a pinhole camera is too dull. The pupil improves the brightness of the image by increasing the size of the pinhole. However, the image is now out of focus. Explain how the pupil might sharpen the image. 4. Name the three main parts of a refracting telescope. 5. Calculate the magnification of the refracting telescope using the formula below if the focal length of the objective lens is 20cm and the focal length of the eyepiece lens is 5cm. Show full working. Magnification = (Focal Length of Objective Lens) / (Focal Length of Eyepiece Lens) Page 11
Where appropriate answer the questions in this homework in full sentences in the spaces provided. Light and Sound Homework 4 Sound and the Ear 1. Complete the following table: Part of the ear What it does Ear Drum Transmit sounds from the middle ear to the inner ear Semicircular Canals Converts the sound vibrations into electrical signals 2. Complete the following passage: Sound is caused by v and needs a m to travel along. 3. On the grid below draw a trace of higher frequency than the one shown, but with the same volume. 4. On the grid below draw a trace of lower volume than the one shown, but with the same frequency. Page 12
Complete the summary when instructed by your teacher. Use your learning outcomes and notes to help you. Unit Summary 1. The speed of light in air/vacuum is m/s. 2. A piece of glass that allows light to pass through is t. 3. Light down as it passes from air into another transparent material. 4. is the change in speed of light as it passes from one medium to another. 5. During refraction if the incident angle is not 90 the ray will change as it crosses the boundary of the two materials. 6. The is an imaginary line drawn at 90 to where the ray strikes. 7. All angles should be measured from the. 8. As light passes from Perspex to air the ray turns from the normal. 9. The or is where the rays converge. 10. The is measured from the focus to the centre of the lens. 11. When an image is tuned upside down it is said to be. Page 13
Complete the summary when instructed by your teacher. Use your learning outcomes and notes to help you. 12. When an image is flipped horizontally it is said to be. 13. The opposite of diminished is. 14. A image can be projected onto a screen whereas a image cannot. 15. A convex lens can be used to m small print. 16. The main parts of the human eye are the c i, p, l, c m, eye m which are used to swivel the eye, r, y s, b s, o n. 17. Complete the table. Part of Eye What it does Cornea the light-sensitive screen at the back of the eye Pupil coloured part of eye that controls the size of the pupil Lens transmits electrical signals to the brain controls the curve of the convex lens inside the eye Page 14
Complete the summary when instructed by your teacher. Use your learning outcomes and notes to help you. 18. A is when the eye lens changes thickness to f on near and far objects. 19. The eye lens is for distant objects and for nearby objects. 20. Two types of eye defects are and sighted. 21. People who are cannot focus on nearby objects. They see a blurry image. 22. People who are cannot focus on distant objects. They see a blurry image. 23. A convex lens will correct and a concave lens will correct. 24. When your surroundings become dimmer, the pupil in your eye gets l. 25. The blind spot has no l sensitive cells and is located where the o n meets the r. 26. An optical illusion is a f or d visual impression. 27. The image formed on the screen in a pinhole camera is u down and r. Page 15
Complete the summary when instructed by your teacher. Use your learning outcomes and notes to help you. 28. When the pinhole in a pinhole camera is large the image is not s. 29. The image of a pinhole can be made sharper by the use of a c l. 30. The aperture of a camera is similar to the p in the eye. 31. Camera film or image sensors are similar to the r in the eye. 32. The refracting telescope is made of three parts: the lens, the lens and the tight. 33. The image produced by the refracting telescope can be made brighter by the of the objective lens. 34. When sounds enter the human ear the e vibrates. 35. The three small bones in the middle ear transmit sound vibrations to the i ear. 36. The cochlea converts the sound vibrations into e signals. These signals are carried by a n to the b. 37. The semicircular canals are required for b. 38. Sound is caused by v. Page 16
Complete the summary when instructed by your teacher. Use your learning outcomes and notes to help you. 39. Sound needs a m to travel through. 40. Sound travels more easily through s than l and g. 41. Frequency is a measure of the p of a sound. 42. Plucking a stretched string harder increases the a of the sound produced. 43. Shortening a stretched string increases the f of the sound produced when the sting is plucked. 44. Making a stretched string less tight will the frequency of the sound produced when the string is plucked. Page 17