LIGHT-POST 5

CLASS 8 CHAPTER 16
Light
Day 5


Dear Learners,

In the previous blogs, we have learned about light. Let me help you to recall few important points that were discussed in previous blogs.

1. Luminous and Non-luminous objects.
2. Laws of reflections.
3. Regular and Irregular reflection.
4. Real and Virtual Image.
5. Formation of images by plane mirror.
6. Ray diagram for the formation of image by plane mirror.
7. Characteristic of image formed by a plane mirror

Today, we will  learn about formation of Multiple Images and uses of plane mirror.

Happy Learning!😊

At the end of it, you will be able to:
1. explain formation of multiple images.
2. tell the uses of plane mirror.



MULTIPLE IMAGES 

Most of us  have visited Salon for hair cut. How many images are seen???
You get to see many images  formed form single object. . 


When two mirrors are placed inclined at an angle to each other many images of the object placed before them are seen. This because  the image formed in one mirror acts as the object for the other.


Do you know???  

1. The number of images seen depends upon the angle at which the two mirror are placed. 
2. When the two mirror are placed parallel to each other,  large number of images are seen.
3. When the mirrors are placed at right angles  to each other, three images of the object are seen.
4. To find out how many images are formed when plane mirrors are tilted at an angle, use the formula N=360/a-1 , wherein N is the number of images formed and a is the given angle.

When the two mirror are placed at right angles to each other

When an object is placed in front of two plane mirrors placed at right angles to each other, three images are formed.


When the two plane mirrors are placed parallel to each other

This process of image formation continues and infinite number of images are formed in the mirror. Only first few images are sharp and can be seen clearly.



USES OF PLANE MIRROR

Plane mirrors are commonly used 

1. as a dressing mirror or looking mirror.
2. for making kaleidoscope and periscope.
3. as a reflector in solar cooker


Home Assignment
1. Read page no 254, 255.
2.do orally, questions no 1, 2, given on page 256

Comments

  1. Ojas punjMay 1, 2020 at 11:04 AM

    Good morning ma'am . I"m Ojas Punj

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  2. Akshat RauthanMay 1, 2020 at 11:05 AM

    Good morning ma'am I'm akshat Rauthan class 8D

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  3. UnknownMay 1, 2020 at 11:07 AM

    Good morning ma'am I am Alan Richard

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  4. Maanvik SoodMay 1, 2020 at 11:07 AM

    Good morning ma'am this is maanvik sood

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  5. ROHANMay 1, 2020 at 11:08 AM

    Good morning ma'am I am Rohan Bisht

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  6. Ronald Jo JosephMay 1, 2020 at 11:09 AM

    Good morning ma'am. I am Ronald Jo Joseph

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  7. Ojas SabherwalMay 1, 2020 at 11:11 AM

    Good morning ma'am I am Ojas Sabherwal

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  8. JoelMay 1, 2020 at 11:12 AM

    Good morning ma'am I am Tumeti Sushaun Joel of class 8D

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  9. Gurdev SinghMay 1, 2020 at 11:13 AM

    Good morning ma'am, I am Gurdev Singh Class 8-D

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  10. Achyut TripathiMay 1, 2020 at 11:13 AM

    Good morning Ma'am I am Achyut Tripathi

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  11. PreetikaMay 1, 2020 at 11:16 AM

    GOOD MORNING BOYS!

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  12. PreetikaMay 1, 2020 at 11:17 AM

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  13. DeependraMay 1, 2020 at 11:21 AM

    Good morning mam. This is DEEPENDRA KUMAR SINGH.8-D

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  14. AnonymousMay 1, 2020 at 11:22 AM

    Good morning mam I am Isaac Visscher class 8D

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  15. AnonymousMay 1, 2020 at 11:22 AM

    Good afternoon mam I am Isaac Visscher class 8-D

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  16. PrabhgunMay 1, 2020 at 11:23 AM

    GOOD MORNING MAM I AM PRABHGUN SINGH CHOPRA

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  19. Shaurya KhatriMay 1, 2020 at 11:35 AM

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  20. Utkrisht suraliyaMay 1, 2020 at 11:39 AM

    Gm mam I'm utkrisht Suraliya 8d

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  21. AnonymousMay 1, 2020 at 11:45 AM

    Good morning mam I am kartik of class 8-D

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  22. Riddhesh S. LodhiMay 1, 2020 at 11:49 AM

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  24. Mohd Zulqar NainMay 1, 2020 at 11:57 AM

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  27. AmaanMay 1, 2020 at 12:31 PM

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