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R1 in a lens is positive or negative?

Posted by Tushar Dulloo 1 year, 1 month ago

CBSE > Class 12 > Physics

1 answers

Krish Agrawal 1 year ago

The sign conventions for the radii of curvature (R1 and R2) for lenses are as follows: 1. **Convex Lens (Diverging Lens)**: - R1 (the radius of curvature of the first surface) is considered positive if the center of curvature is on the same side as the incident light (opposite to the direction of incoming light). - R2 (the radius of curvature of the second surface) is considered negative. 2. **Concave Lens (Converging Lens)**: - R1 (the radius of curvature of the first surface) is considered negative. - R2 (the radius of curvature of the second surface) is considered positive if the center of curvature is on the same side as the incident light (opposite to the direction of incoming light). These conventions are used in lens formula and mirror formula calculations to determine the sign of focal lengths and object distances.

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What is lantanoid contraction

Posted by Charan Teja 1 year, 1 month ago

CBSE > Class 12 > Chemistry

1 answers

Keshav Chauhan 10 months, 3 weeks ago

When we move from 3d to 4d and 4d to 5d... The electrons start to be filled in the f subshell. As the screening power of the electrons of the f subshell is very poor, that's why there is regular decrease in the atomic radii of these elements, this is called lanthanoid contraction

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What does the phrase 'to skin me' mean

Posted by Kashish Pathania 1 year, 1 month ago

CBSE > Class 12 > English Core

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Contribution of John marshal and martimer wheeler in Indian archaeology

Posted by Supriya Nath 1 year, 1 month ago

CBSE > Class 12 > History

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Kaal Lu 1 year, 1 month ago

John Marshall and Mortimer Wheeler made significant contributions to Indian archaeology: 1. **John Marshall**: - Marshall was the Director-General of the Archaeological Survey of India (ASI) from 1902 to 1931. He played a crucial role in systematizing archaeological research in India. - Under his leadership, the ASI conducted extensive excavations at various sites, including Mohenjo-Daro and Taxila, leading to the discovery of the Indus Valley Civilization. - He emphasized the importance of preservation and documentation of archaeological finds, which laid the foundation for modern archaeological practices in India. 2. **Mortimer Wheeler**: - Wheeler succeeded Marshall as the Director-General of ASI. He brought innovative techniques to Indian archaeology. - Wheeler introduced the grid system for excavations, which improved the accuracy of documenting findings and stratigraphy. - His work at sites like Harappa and Arikamedu furthered our understanding of India's ancient history. - Wheeler also emphasized the training and involvement of Indian archaeologists in excavation work, contributing to the development of a skilled workforce in the field. Both Marshall and Wheeler made substantial contributions to the study of India's archaeological heritage and its history.

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Trace the technologies that were used for making beads by Harappans.

Posted by Mahem Bankai 1 year, 1 month ago

CBSE > Class 12 > History

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Devjyoti Bravia answers

Posted by Rohan Rajput 1 year, 1 month ago

CBSE > Class 12 > English Core

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Jahangir Alom 1 year, 1 month ago

2+3

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Author name of the poem kepping quiet

Posted by Harkirat Kaur 1 year, 1 month ago

CBSE > Class 12 > English Core

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Kashish Gurawalia 1 year, 1 month ago

Pablo Naruda poet of poem keeping quiet

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Jasleen Gill 1 year, 1 month ago

Pablo Naruda

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Imagine you are Hana narrate the chapter from your point of view

Posted by Pronay Das 1 year, 1 month ago

CBSE > Class 12 > English Core

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did the people at Gemini studios have any particular political affiliations

Posted by Naresh Choudhary 1 year, 1 month ago

CBSE > Class 12 > English Core

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Mr lamb stands as a symbol of optimism and hope support your answer with example from the text

Posted by Subhanshu Sharma 1 year, 1 month ago

CBSE > Class 12 > English Core

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MCQ Qunestion

Posted by Harshit Bhargava 1 year, 1 month ago

CBSE > Class 12 > Economics

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Tarun Kumar 1 year, 1 month ago

What is moter devlopment

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In what ways do you think that the Western Indian manuscript painting tradition guided the development of miniature painting traditions in Rajasthan

Posted by Krishna Kant Gaur 1 year, 1 month ago

CBSE > Class 12 > Painting

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In what ways do you think that the western Indian

Posted by Krishna Kant Gaur 1 year, 1 month ago

CBSE > Class 12 > Painting

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Question 1: A lens has a refractive index of 1.5 and a radius of curvature of 15 cm for one surface and 20 cm for the other surface. Calculate the difference in curvature between the two surfaces using the lens maker's formula Question 2: A concave lens with a refractive index of 1.4 is required to have a focal length of -12 cm. Determine the radil of curvature for the two lens surfaces using the lens maker's formula. Question 3: A biconvex lens with a refractive index of 1.6 has a known focal length of 25 cm. Calculate the difference in radii of curvature for its two surfaces using the lens maker's formula. Question 4 (Easy): A plano-concave lens has a refractive index of 1.2. The radius of curvature of the curved surface is 18 cm, and the flat side has a radius of curvature of infinity, Calculate the focal length of the lens using the lens maker's formula. Question 5 (Easy): A converging lens has a refractive index of 1.6. The radius of curvature of one surface is 12 om, and the radius of curvature of the other surface is 15 cm. Calculate the focal length of the lens using the lens maker's formula.

Posted by Tushar Dulloo 1 year, 1 month ago

CBSE > Class 12 > Physics

1 answers

Krish Agrawal 1 year ago

To answer each of your questions, we can use the lens maker's formula, which is given by: \[ \frac{1}{f} = (n - 1) \left( \frac{1}{R_1} - \frac{1}{R_2} \right) \] Where: - \( f \) is the focal length of the lens. - \( n \) is the refractive index of the material. - \( R_1 \) is the radius of curvature of the first surface. - \( R_2 \) is the radius of curvature of the second surface. Let's solve each of your questions: **Question 1:** Given \( n = 1.5 \), \( R_1 = 15 \, \text{cm} \), and \( R_2 = 20 \, \text{cm} \), we need to calculate the difference in curvature between the two surfaces. Using the lens maker's formula, we can calculate the focal length, and then the difference in curvature. 1. Calculate \( \frac{1}{f} \) using the formula with the given values. 2. Once you find \( \frac{1}{f} \), calculate the focal length \( f \) by taking the reciprocal. **Question 2:** Given \( n = 1.4 \) and \( f = -12 \, \text{cm} \), we need to determine the radii of curvature for the two lens surfaces. Using the lens maker's formula, you can calculate \( R_1 \) and \( R_2 \). 1. Rearrange the lens maker's formula to solve for either \( R_1 \) or \( R_2 \). 2. Plug in the known values and solve for \( R_1 \) and \( R_2 \). **Question 3:** Given \( n = 1.6 \) and \( f = 25 \, \text{cm} \), we need to calculate the difference in radii of curvature for its two surfaces. Again, use the lens maker's formula to calculate \( R_1 \) and \( R_2 \). **Question 4:** Given \( n = 1.2 \), \( R_1 = 18 \, \text{cm} \), and \( R_2 = \infty \) for a flat side, calculate the focal length using the lens maker's formula. **Question 5:** Given \( n = 1.6 \), \( R_1 = 12 \, \text{cm} \), and \( R_2 = 15 \, \text{cm} \), calculate the focal length using the lens maker's formula. For each question, perform the calculations as described above, and you will have the answers you need. If you have any specific values to calculate or encounter any issues, feel free to ask for further assistance.

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Classify industries on the basis of raw materials used. Explain each one of them with examples.

Posted by Khushi Kanwar 1 year, 1 month ago

CBSE > Class 12 > Geography

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Pen limit pen limited invited application for 75000 equity share of 100 is 20 on application 30 on allotment 20 on 1st call 30 on 2nd call application were received for 90000 equity share which were allotted on prorata basis A shareholder who applied for 1800 share fail to pay on first call and second

Posted by Badal Singh 1 year, 1 month ago

CBSE > Class 12 > Accountancy

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Wayne and tim are partner total interest on loan extended by wayne to firm is 20000 firm has net profit of 5000 the capital of wayne and tim are in the ratio of 2:3 what will be Wayne's share of profile or loss?

Posted by Mahi Singh 1 year, 1 month ago

CBSE > Class 12 > Accountancy

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State the meaning of commune

Posted by Suwashna Khokhar 1 year, 1 month ago

CBSE > Class 12 > Economics

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Explain any four factors that make European union a strong organisation

Posted by Aron Gurung 1 year, 1 month ago

CBSE > Class 12 > Political Science

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Kashish Gurawalia 1 year, 1 month ago

1. Common foreign and security policy 2. Corporation 3. Development and security 4. Creation common identity and flag

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At wipro project

Posted by Muskan Nothing 1 year, 1 month ago

CBSE > Class 12 > Business Studies

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Account Deleted 1 year, 1 month ago

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What is organic farming and advantages and disadvantages of organic farm

Posted by Kamal Buttar 1 year, 1 month ago

CBSE > Class 12 > Economics

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What is dry cell

Posted by Krushnakant Nayak 1 year, 1 month ago

CBSE > Class 12 > Chemistry

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Keshav Chauhan 10 months, 3 weeks ago

Dry cell is a primary cell. It works as voltaic cell. It is used in clocks, remotes,etc.

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Aa Zz 1 year, 1 month ago

Which do not have liquid

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3 marks 25 (a) In this painting three women are portrayed in the center of the picture plane with yellow, white and red saris, placed within the background of trees and nature. A dark black and brown portrayal of a woman behind the tree, seems to be in a resting mood also catches the eyes of the viewers. Identify and name the artist. (ii) Name the painting and the common spice depicted in it? (iii) Does the massive power of rural women reflect in the subject matter of the painting? Explain logically with your artistic point of view.

Posted by Yukti A 1 year, 1 month ago

CBSE > Class 12 > Painting

2 answers

Jiggu Jiggu 1 year ago

Artist 1 Ans

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Palak Sharma. 1 year, 1 month ago

2.Haldi grinder by Amrita shergill

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How did the champaran peasants react when they here that a Mahatma had come to help them .

Posted by Riya Gupta 1 year, 1 month ago

CBSE > Class 12 > English Core

2 answers

Akash Pal 1 year, 1 month ago

How is everything

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Akash Pal 1 year, 1 month ago

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To what extent were agricultural practices transformed in the period 600 BC to 600 AD

Posted by Sheetal Rana 1 year, 1 month ago

CBSE > Class 12 > History

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Sheetal Rana 1 year, 1 month ago

To what extent were agricultural practices transformed in the period 600 BC to 600 AD

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The two lines X=ay+b, Z=cy+d and X = a'y+b' , Z=c'y+d' are perpendicular to each other , if (a) a/a' + c/c' = 1 (b) a/a' + c/c' = -1 (c) aa' + cc' = 1 (d) aa' + cc' = -1

Posted by Sanchitha Salunkhe 1 year, 1 month ago

CBSE > Class 12 > Mathematics

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Ankush Thakur 1 year, 1 month ago

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What is share holder fund

Posted by Sneha Nagar 1 year, 1 month ago

CBSE > Class 12 > Accountancy

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What are the various features of capital market?

Posted by Taufik Ansari 1 year, 1 month ago

CBSE > Class 12 > Business Studies

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Meera is a sprinter who participates in various competitions

Posted by Ruchi Gehlot 1 year, 1 month ago

CBSE > Class 12 > Physical Education

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Riya Saini 1 year, 1 month ago

What is mean by rickets

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You are Karthika/Karthik of channai.of late, chain-snatching incidents are increasing in the city.write a letter to the editor of the New Indian express drawing the attention of the concerned authorities.also give suggestions.

Posted by Anusha Limboo 1 year, 1 month ago

CBSE > Class 12 > English Core

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Aditya Kumar Gupta 1 year, 1 month ago

Don't post personal information, mobile numbers and other details.
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Jannipalleruka.Prasanya Prasanya 1 year, 1 month ago

The Third level

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