1 / 25

Journal #81 April 22, 2011

Journal #81 April 22, 2011. You do not need to copy this paragraph. Use the concave and convex mirrors on your table. Start with the mirror very close to your eye and slowly back it away . Describe the changes to your image until the mirror is a full arm’s length away.

garson
Download Presentation

Journal #81 April 22, 2011

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Journal #81 April 22, 2011 You do not need to copy this paragraph • Use the concave and convex mirrors on your table. Start with the mirror very close to your eye and slowly back it away. Describe the changes to your image until the mirror is a full arm’s length away

  2. Answer to Journal #81 • Concave: The image starts off very close to regular size and increases in size. Image becomes completely blurred. Image reforms and is inverted and enlarged. It becomes reduced the farther away you move beyond this point. • Convex: The image starts off very close to regular size but reduces as the mirror is pushed back. Also, image is not a true representation of object… slightly skewed.

  3. Plane Mirror Reflection is on top of incident light Image formed is: Virtual Upright Same Size

  4. Try to fill in this chart from memory… best way to study!

  5. Answer Key to Table

  6. How to make a study game Take 4 sheets of blank paper and fold them in half 3 times to create 8 equal sized sections Cut each of the rectangular shapes made by the creases

  7. How to make a study game Lay out the individual rectangles in a 4 by 8 grid

  8. How to make a study game Remove the bottom row and save them as extras (in case you make a mistake)

  9. How to make a study game In the first column, write each of the seven possible situations for mirrors AND/OR draw the set up

  10. How to make a study game On the back of those same cards, write IN PENCIL the answers for that card

  11. How to make a study game In the other columns, write the three answers each on a separate card for the situation on the left

  12. How to PLAY a study game Collect all of the answer cards in a single stack and all of your setup cards in a different stack

  13. How to PLAY a study game Shuffle both stacks, then deal out the setup cards in random order

  14. How to PLAY a study game Place all of the answer cards on the table Turn over the setup cards and check your answers!

  15. Journal #82 April 25, 2011 WITHOUT USING YOUR NOTEBOOK!!! • If you know the focal length of a concave mirror, where should you place an object so that its image is upright and larger compared to the object? • Will this produce a real or virtual image?

  16. Journal #82 Answer • Place the object between the focal point and the mirror. • The image will be virtual

  17. Lens/Mirror Equation • (units of length MUST match) • f stands for focal length • di is the distance from the mirror/lens to the image • do is the distance from the mirror/lens to the object

  18. Image Height • Magnification of an image can be found by a series of ratios between the distances of objects and their images and their respective heights as shown below.

  19. Helpful Hints for Mirror Probs • In the formula, the numbers can tell you the characteristics of the image: • Size • Reduced ( |hi| < ho ) • Same Size ( |hi| = ho ) • Enlarged ( |hi| > ho ) • Orientation • Upright (hi positive) • Inverted (hi negative) • Type of Image • Real (di positive, in front of mirror) • Virtual (di negative, behind the mirror) • Focal point for concave mirror is always positive. • Focal point for convex mirror is always negative.

  20. Example problem 1 • A concave mirror has a radius of 28cm. An 15cm tall object is placed 25cm from the mirror. Describe the image formed. What will be the height and position of the image?

  21. Example problem 2 • A convex mirror has a focal length of 32cm. An 17cm tall object is placed 1.0m from the mirror. Describe the image formed. What will be the height and position of the image?

  22. HW Problems • P. 469 13-16 • P. 472 17-21

  23. P. 469

  24. P. 472

  25. Spherical Aberration Special Note: • Parallel light rays that are far from the principal axis are not reflected by spherical mirrors to converge at the focal point. This defect is called spherical aberration. To avoid this dilemma, spherical mirrors have been replaced with parabolic mirrors in devices such as telescopes that require extreme accuracy and focus.

More Related