Physics Learning Guide Name: Instructions: Using a pencil, complete the following notes as you work through the related lessons. Show ALL work as is explained in the lessons. You are required to have this package completed BEFORE you write your unit test. Do your best and ask questions if you don t understand anything! Light 1. Two people create standing waves using a skipping rope. In the first trial they make long standing waves by slowly moving their arms up and down. Without changing anything but the speed of their arm movement, they then create the second, shorter, standing wave. Fill in the boxes below and then relate these waves to light. Wave Created Circle LONG or SHORT Wavelength (label wavelength directly on the diagram) LONG Or SHORT Does it take MORE ENERGY or LESS ENERGY to create this wave? MORE ENERGY Or LESS ENERGY HIGH Frequency or LOW frequency? HIGH Or LOW LONG Or SHORT MORE ENERGY Or LESS ENERGY HIGH Or LOW a. If wavelength gets shorter, the frequency gets (lower or higher). b. In your own words describe what it means to be a high frequency wave. c. Blue light has a (longer or shorter) wavelength than red light. d. Blue light has a (higher or lower) frequency than red light. e. Based on the diagrams above explain why blue light contains more energy than red light. Page 1 of 20
2. The following types of electromagnetic radiation in order from lowest to highest energies are: (ultraviolet, radio, infrared, X-rays, black light, red light). 3. The wavelength (decreases or increases) as the frequency of an electromagnetic wave increases. 4. The type of electromagnetic radiation these things use or produce is: your eyes your skin a tanning booth a radio 5. As the wavelength of electromagnetic radiation decreases, what happens to: frequency energy 6. How does visible light compare with X-rays in terms of: wavelength frequency energy 7. What is white light? What is it made up of? Page 2 of 20
8. Our eyes can only detect the visible spectrum. What is the visible spectrum and how does it relate to white light? 9. When light passes through a medium such as glass or water, it bends or refracts. Dispersion occurs when white light undergoes refraction and separates into the entire visible spectrum as shown by the prism below. Use the diagram to answer the questions that follow. a. Take a ruler and continue the path that the white light would have followed without the prism. b. What colour of light bent or changed direction the most from the original path of the white light? (this is called refraction). c. The wavelength of the light in (b) is (small or large) and has a (higher or lower) frequency. d. What colour of light bent or changed direction the least from the original path of the white light? e. The wavelength of the light in (d) is (small or large) and has a (higher or lower) frequency. f. Summarize: Describe the how the properties of the violet light cause it to bend or refract more than the red light. Page 3 of 20
10. A prism is usually made of glass and causes white light to separate. What is the prism that causes a rainbow? 11. Every now and again we get lucky enough to witness a double rainbow like the one in the photo below: a. What do you notice about the order of the colours in each rainbow? Look closely. b. We know that a raindrop is the prism that is responsible for the colours of the rainbow. Come up with your own theory as to why the colours of the two rainbows have been reversed. 12. The colours of a rainbow in order are 13. Dispersion is 14. Different colours of light have wavelengths. 15. light has the longest wavelength and the energy of visible light while light has the shortest wavelength and the energy of visible light. Page 4 of 20
16. Light Rays and the Pinhole Camera a) Draw a ray diagram that explains why the image formed by a pinhole camera is upside down. b) Why is+ the image created so faint or dim? Light Transmission: 17. List each of the items you tested under one of the three headings (see the tutorial entitled 3.2 Light Transmission). Easily allows light through Allows some light through Does not allow light through Page 5 of 20
18. Transparent material allows. Translucent material allows. Opaque material allows 19. On the picture shown, draw the light rays and label the shadows formed. Then answer the questions: Location of opaque object Is the shadow BIGGER or SMALLER? Object further from light BIGGER or SMALLER Object closer to light BIGGER or SMALLER a. Describe what happens to the size of the shadow when the object is moved closer to the light or the screen is moved further away. Page 6 of 20
20. Complete the table below by describing where you think the sun is located in relation to the picture. Then discuss whether the sun is low or high in the sky based on the shadow. Use a ruler and a pencil to trace a ray to show where you think the sun must be. Picture: draw a ray using a ruler to help show where the sun is Where is the sun (eg. left, right, upper right, lower left etc.) Is the sun high in the sky? Low in the sky? Or in between? What time of day is it? Page 7 of 20
21. Fake photos. Using the properties of light, explain why the photos below are fake. Fake Photo: Explanation: 22. A flower is red because 23. Black clothes make you feel hotter on a sunny day because Page 8 of 20
Reflection of Light: 1. Draw the path that the light rays follow from the object (the bird) to the person. Then use the diagram to explain how a periscope works. a. What angle should the mirrors be positioned at for the above periscope to work properly? degrees b. How would letters and text look to the person in the above diagram? Why? c. How would we have to change the periscope if we only had one mirror? How would letters and text look to the person in this case? Page 9 of 20
2. A laser creates a beam that is aimed at a mirror as shown below. Using the fact that the laser will reflect such that the angle of incidence = the angle of reflection, complete the path that the laser beam will follow through the maze of mirrors. Not all mirrors need to be included and the laser beam should end up at the detector if all goes right. a. Use a protractor to measure each angle of incidence and angle of reflection and label these onto the diagram above. 3. Draw how each incident ray will properly reflect. Page 10 of 20
4. Examine the photos below and explain why one perfect represents almost perfect reflection, while the other is slightly blurry. Reflection Ray diagram to explain why reflection is perfect or blurry Perfect Reflection Blurry Reflection 5. Smooth surfaces appear shiny because 6. What type of mirror can flip or invert images so that they appear upside down? Concave or Convex? 7. What type of mirror is capable of magnification so that the image appears larger than the original object? (hint: if you can find a make-up mirror take a closer look at how it is curved) Page 11 of 20
8. Examine the images in the mirrors below. a. Which mirror shown below is convex? How do you know? b. Which mirror shown below is concave? How do you know? Refraction of Light: 9. When light strikes another medium at an angle, such as glass or water, the rays bend at the entry point due to. Page 12 of 20
10. What is the difference between REFRACTION and REFLECTION (in terms of the path of light)? 11. When light rays slow down (when they pass into a more optically dense material such as water or glass), they bend in TOWARDS the Normal line so that the angle decreases. When light rays speed up (leaving glass and out into air), they bend AWAY from the Normal line so that the angle increases. Examine the picture below. Using the rules above, complete ray diagram below by predicting how the incoming light will bend as it passes into and out of the prism below. Draw the rays directly onto the diagram and include Normal lines at both the entry and exit points. Page 13 of 20
12. Examine the diagrams below, then summarize using the questions below as your guide. a. What is the only type of lens that can produce an image that is flipped or inverted? Convex or Concave? b. What is the only lens that create a magnified image (appears larger than the original object)? c. What type of lens always produces a smaller, upright image? Page 14 of 20
13. Draw in the light rays as they pass through the lens 14. Complete the chart for a concave lens. Position of object from lens Size of image Orientation of image Any distance from lens 15. Draw in the light rays as they pass through the lens Page 15 of 20
16. Identify the type of lens shown below. Explain how you can be sure? Image Type of Lens How do you know? (what is it about the image?) Convex Or Concave Convex Or Concave Convex Or Concave Page 16 of 20
17. What property of light is demonstrated in each picture below? Reflection or Refraction. Explain your answer. Picture Reflection of Refraction? How do you know? Page 17 of 20
Picture Reflection of Refraction? How do you know? Your Eye: 1. Label the following parts of the eye and give a brief description of each part. Page 18 of 20
2. Converging lenses are said to bring the light rays closer together after they pass through the lens. Converging lenses bring the light rays further apart. Examine the pictures below and identify the lens as diverging or converging? Lens Diverging or Converging 3. The eye shown below is said to be near-sighted or myopic. a. Examine the picture. Does the light focus before or after the retina? b. What kind of lens would adjust these rays so that the light focuses on the retina? Diverging or converging? Explain Page 19 of 20
4. The eye shown below is said to be far-sighted or myopic. a. Examine the picture. Does the light focus before or after the retina? b. What kind of lens would adjust these rays so that the light focuses on the retina? Diverging or converging? Explain Page 20 of 20