LIGHT-(P0ST-1)

CLASS 8 CHAPTER 16
Light

“If you are the light, you cast away the darkness.” ManHee Lee😊 

Dear Learners,

Happy Learning!😊

At the end of today topic, you will be able to:
1. Define Light.
2. Expain  Reflection of Light and terms related to it.
3. state the laws of reflection.

Important Instructions: 

1. Make the new entry of the chapter in your index.
2. Start the chapter from a  fresh page. 
3.Diagrams need to be drawn with pencil and should be well labelled.

Lets begin!

 click on the link below for an introduction to LIGHT.


We see a variety of objects  around us. However, we are unable to see anything in a dark room. On lighting up the room, things become visible. 

What makes things visible???

During the day,  sunlight helps us to see object. An object reflects light that falls on it. This reflected light is received by our eyes, enabling  us to see it.

Light is an invisible  form of energy that enables us to see things around. We  can see  luminous bodies even in the dark because they emit light whereas the non-luminous bodies cannot be seen in dark. 

Luminous and Non-luminous Objects:


Here, we need to understand that when light falls on an object or any surface, it may pass through it, it may get absorbed by it or it may bounce back after striking the object or surface.

A highly polished surface, such as a mirror, reflects most of the light falling on it. This is called as reflection of light.

Reflection of Light: Bouncing back of light rays after hitting any surface is called reflection of light

  A ray of light falls on a flat mirror and gets reflected from it,and follows  the laws of reflection. 

Laws of Reflection:

Law 1: The angle of incidence is equal to the angle of reflection. (∠i = ∠r)
Law 2: The incident ray, the reflected ray and the normal lie on the same plane.



Link for Laws of Reflection: https://www.youtube.com/watch?v=YFgSHRCRa6k

Terms related to reflection of light-

1. Incident ray of light: The ray of light which falls on an object is called Incident ray of light.

2. Reflected ray of light: The ray of light which gets bounced back or reflected from the surface of an object is called reflected ray of light.

3. Angle of incidence: The angle between the incident ray and the normal at the point of incidence is  called angle of incidence ∠i.

4. Angle of reflection: The angle between the reflected ray and the normal is called angle of reflection ∠r.

Experimental Proof for Law of Reflection: 


. Click on the following link for more details.



Home Assignment:
1. Read page no 247, 248, 249


 ASSEST QUESTION


  A ray of light is incident towards a plane mirror at an angle of 30-degrees . What will be the angle of reflection?

 a) 30 degrees  b)70 degrees c) 50 degrees
d) 0 degrees


Comments

  1. Ojas punjApril 27, 2020 at 7:09 AM

    Good morning Ma'am. I'm Ojas Punj

    ReplyDelete
  2. Abhay Singh UpmanyuApril 27, 2020 at 7:18 AM

    Good morning ma'am I am ABHAY SINGH UPMANYU of 8D

    ReplyDelete
  3. Abhishek SharmaApril 27, 2020 at 7:36 AM

    Good morning ma'am I am abhishek sharma

    ReplyDelete
  4. Ronald Jo JosephApril 27, 2020 at 8:14 AM

    Good morning ma'am. I am Ronald Jo Joseph

    ReplyDelete
  5. Vishnu VardhanApril 27, 2020 at 8:26 AM

    Good morning mam I am vishnu Vardhan

    ReplyDelete
  6. Jacob TombingApril 27, 2020 at 8:35 AM

    Good morning ma'am, Jacob here.

    ReplyDelete
  7. Ashaan Anurag lallApril 27, 2020 at 8:35 AM

    Good morning mam I am Ashaan Anurag lall

    ReplyDelete
  8. unknownApril 27, 2020 at 8:40 AM

    I am Hitesh Vijay Nitnaware

    ReplyDelete
  9. Mohit KumarApril 27, 2020 at 9:01 AM

    Good morning mam. I'm Mohit Kumar.

    ReplyDelete
  10. Aditya JaisonApril 27, 2020 at 9:13 AM

    Good morning ma'am....
    I am Aarush of class 8D

    ReplyDelete
  11. Arpit Jonathan PillayApril 27, 2020 at 9:13 AM

    Good morning Maam I am ARPIT JONATHAN PILLAY

    ReplyDelete
  12. Varun negiApril 27, 2020 at 9:16 AM

    Good morning Ma'am I am Varun negi

    ReplyDelete
  13. Akshat RauthanApril 27, 2020 at 9:20 AM

    Good morning ma'am I'm akshat Rauthan

    ReplyDelete
  14. AnonymousApril 27, 2020 at 9:24 AM

    Good morning mam I am kartik of class 8-D

    ReplyDelete
  15. Akash DcostaApril 27, 2020 at 9:27 AM

    Good morning mam I am Akash Dcosta 8D

    ReplyDelete
  16. Simon josephApril 27, 2020 at 9:31 AM

    Good morning mam I am simon joseph

    ReplyDelete
  17. ROHANApril 27, 2020 at 9:34 AM

    Good morning ma'am I am Rohan Bisht

    ReplyDelete
  18. Shaun DsouzaApril 27, 2020 at 9:36 AM

    Good morning , my name is Shaun Dsouza

    ReplyDelete
  19. PrabhgunApril 27, 2020 at 9:38 AM

    Good morning , my name is Prabhgun

    ReplyDelete
  20. AnonymousApril 27, 2020 at 9:42 AM

    Good morning mam I am Anas Ahmad

    ReplyDelete
  21. JoelApril 27, 2020 at 9:42 AM

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

    ReplyDelete
  22. Maanvik SoodApril 27, 2020 at 9:42 AM

    Good morning ma'am this is Maanvik Sood

    ReplyDelete
  23. Janav jainApril 27, 2020 at 9:42 AM

    Good morning Ma’am
    JanavJain

    ReplyDelete
  24. Riddhesh S. LodhiApril 27, 2020 at 9:43 AM

    Good morning ma'am I am Riddhesh S. Lodhi of class 8th D

    ReplyDelete
  25. AnonymousApril 27, 2020 at 9:45 AM

    Good morning mam I am Isaac Visscher class 8 D

    ReplyDelete
  26. Achyut TripathiApril 27, 2020 at 9:47 AM

    Good morning Ma'am I am Achyut Tripathi

    ReplyDelete
  27. AdityaApril 27, 2020 at 9:48 AM

    Good morning ma'am I am aditya khare

    ReplyDelete
  28. UnknownApril 27, 2020 at 9:49 AM

    Good morning maam I am Shaurya khatri

    ReplyDelete
  29. Aron haokipApril 27, 2020 at 9:52 AM

    Good morning ma'am I am Aron haokip 8 D

    ReplyDelete
  30. Ojas SabherwalApril 27, 2020 at 9:56 AM

    Good Morning ma'am , I am Ojas Sabherwal

    ReplyDelete
  31. Gurdev SinghApril 27, 2020 at 10:16 AM

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

    ReplyDelete
  32. Krishna GhoshApril 27, 2020 at 10:35 AM

    This comment has been removed by the author.

    ReplyDelete
  33. Utkrisht suraliyaApril 27, 2020 at 11:00 AM

    Gm mam I'm utkrisht Suraliya 8d

    ReplyDelete
  34. Daksh martinApril 27, 2020 at 11:10 AM

    Good morning mam daksh martin here

    ReplyDelete
  35. AmaanApril 27, 2020 at 12:40 PM

    Good afternoon ma'am I am Amaan Richard

    ReplyDelete
  36. UnknownApril 27, 2020 at 1:38 PM

    Good afternoon Ma'am I am Himalay Umarwal

    ReplyDelete
  37. Suman Kumar PurkaitApril 27, 2020 at 5:31 PM

    Good afternoon mam I am Suman Kumar Purkait

    ReplyDelete

Post a Comment

Popular posts from this blog

lesson -cell structure n function ( POST 2)

Image
Good morning boys! In the last class we learnt that- . Cell is the basic structural and functional unit of life. .Depending on the number of cells , organisms can be grouped as unicellular or multicellular. . The size of a cell is related to its functions. LEARNING OUT COMES- By the end of this class you will be able to- .name the three basic parts of a cell and state their functions .distinguish between a eukaryotic and prokaryotic cell Today we are going to learn about CELL STRUCTURE .a A typical cell consists of three basic parts : 1 .  CELL MEMBRANE OR PLASMA MEMBRANE - . It forms the outer boundary of the cell, gives shape and size  to the cell. . It only allows certain selected substances to enter or leave the cell ( it is semi-permeable ). . It separates the cells from one another  and also from the surrounding medium. NOTE - In PLANT CELLS and BACTERIA there is an outer wall surrounding the cell membrane ,it is called the CELL WALL. It gives protection again
Read more

LIGHT-POST 2

Image
Dear Learners, BOYS, WE HAVE A GOOGLE MEET FROM 9am -9.20 am, PLEASE ATTEND IT(THE MEET ID HAS BEEN POSTED ON YOUR CLASS GROUP). AFTER 9.20 ,READ THE BLOG. In the previous blog, we have learned about light and reflection of light. Let me help you to recall few important points 1. Light is a form of energy that enable us to see. 2. There are two laws of reflections.  Today, we will be learning about regular and irregular reflection, real and virtual images. Happy Learning!😊 At the end of it, you will be able to: 1. Differentiate between regular and irregular reflection. 2. Differentiate between real and virtual image. so, lets start the chapter......... When a ray of light falls on a reflecting surface, it get reflected. the amount and the direction of the light reflected depends on the nature of the surface. Depending upon the nature of the reflecting surface, there are two types of reflections. Click the link:  https://www.youtube.com/watch?v=f0NtpGe
Read more

lesson- cell structure and functions (post -5)

GOOD MORNING BOYS!  WE HAVE COMPLETED THE LESSON- CELL STRUCTURES AND FUNCTIONS. -  Complete all the 12 questions-answers shared with you on your class group in your notebook.   DO the following objective questions in your notebook  13.  NAME THE UNICELLULAR ORGANISMS WITH HELP OF THE CLUES GIVEN:  a). Has false feet called pseudopodia.   ..amoeba................... b). Has hair -like structures called cilia.    ..paramecium......................... c). Is spindle -shaped.  ..Euglena...................... d). It causes fermentation in foods containing carbohydrates.   ....yeast.................. e). Is a slipper-shape aquatic animal.   ..paramecium................... f). An  unicellular aquatic animal with a flagellum.  ...Euglena.................... g). An  unicellular aquatic plant with a flagella    ..Chlamydomonas............................................ 14.  WRITE THE SCIENTIFIC TERMS FOR THE FOLLOWING: a) The power house of a cell.   ...mitochondria.....
Read more