Rules For Image Formation In Lenses
Rules For Image Formation In Lenses
Only two rays from the same point of an object are needed for image formation and the point where the rays after refraction through the lens intersect or appear to intersect is the image of the object. If they actually intersect each other the image is real and if they appear to intersect the image is said to be virtual. In order to locate the image formed by a lens graphically following rules are adopted
Rays used for ray diagram of Image formation:
1. We choose the ray that is incident parallel to the principal axis. In case of a convex lens, the transmitted ray will pass through the focus, and in case of a concave lens, the transmitted ray’s backward projection will pass through the focus.
2. We choose the ray that passes through the optical centre of the lens. This ray is transmitted without any deviation.
3. A ray passing through first focus or directed towards it, after refraction from the lens becomes parallel to the principal axis (by definition of F).
The point of intersection of any of two of these transmitted rays is the image of the point object.
In the case of lens refraction occurs at both the surfaces, Once at the surface when the ray enters the lens and then at the surface when the ray comes out of the lens. While tracing the rays, we do not show the ray bending at each surface of the lens. Instead, we show the incident rays getting bent at the central, vertical line of the lens because we are using a thin lens.
Which of the following are correct ? (a) If the rays after refraction from the lens actually intersect each other the image is virtual and if they appear to intersect the image is said to be real . (b) While identifying the position of the image formation in case of lens we can choose the ray that passes through the optical centre of the lens. (c) In the case of lens refraction occurs at both the surfaces once when the ray enters the lens and then at the surface when the ray comes out of the lens. | |||
| Right Option : B | |||
| View Explanation | |||
Only _____________rays from the same point of an object are needed for image formation | |||
| Right Option : B | |||
| View Explanation | |||
While identifying the position of the image we can use the ray that is incident parallel to the principal axis.In the case of the concave lens, the transmitted ray’s backward projection will pass through the _________________ . | |||
| Right Option : A | |||
| View Explanation | |||
Students / Parents Reviews [10]
It has a great methodology. Students here can get analysis to their test quickly.We can learn easily through PPTs and the testing methods are good. We know that where we have to practice
Barkha Arora
10thAbout Abhyas metholodology the teachers are very nice and hardworking toward students.The Centre Head Mrs Anu Sethi is also a brilliant teacher.Abhyas has taught me how to overcome problems and has always taken my doubts and suppoeted me.
Shreya Shrivastava
8thMy experience with Abhyas academy is very good. I did not think that my every subject coming here will be so strong. The main thing is that the online tests had made me learn here more things.
Hiya Gupta
8thIt was a good experience with Abhyas Academy. I even faced problems in starting but slowly and steadily overcomed. Especially reasoning classes helped me a lot.
Cheshta
10thOne of the best institutes to develope a child interest in studies.Provides SST and English knowledge also unlike other institutes. Teachers are co operative and friendly online tests andPPT develope practical knowledge also.
Aman Kumar Shrivastava
10thBeing a parent, I saw my daughter improvement in her studies by seeing a good result in all day to day compititive exam TMO, NSO, IEO etc and as well as studies. I have got a fruitful result from my daughter.
Prisha Gupta
8thAbhyas is a complete education Institute. Here extreme care is taken by teacher with the help of regular exam. Extra classes also conducted by the institute, if the student is weak.
Om Umang
10thAbhyas Methodology is very good. It is based on according to student and each child manages accordingly to its properly. Methodology has improved the abilities of students to shine them in future.
Manish Kumar
10thIt was good as the experience because as we had come here we had been improved in a such envirnment created here.Extra is taught which is beneficial for future.
Eshan Arora
8thMy experience was very good with Abhyas academy. I am studying here from 6th class and I am satisfied by its results in my life. I improved a lot here ahead of school syllabus.
