Home » Electromagnetic Waves Class 12 & Optics JEE Questions and Answers

Electromagnetic Waves Class 12 & Optics JEE Questions and Answers

Update on: 09 Jan 2023, 05:38 PM

Electromagnetic Waves Class 12 & Optics JEE Questions and Answers

Many important questions are formed in competitive exams like CUET, JEE, NEET, and boards from Class 12 Physics. Below, we have provided Important Questions from Class 12 Physics Unit 5 and 6, Electromagnetic Waves and optics for your JEE Mains 2023 preparation. You can check it here for revision purposes.

Latest: Electromagnetic Induction and Alternating Currents JEE Questions and Answers

Electromagnetic Waves Class 12 & Optics JEE Mains Questions and Answers

We’ve compiled a list of important questions about the Electromagnetic Waves Class 12 & Optics physics class 12 unit 5 and 6 that you should not miss while studying for your JEE Main Exams.

Q.1. In a single slit diffraction pattern, the distance between the first minimum on the left and the first minimum on the right is 5 mm. The screen on which the diffraction pattern is displayed is at a distance of 80 cm from the slit. The wavelength is 6000 Å. The slit width (in mm) is about

(a) 0.576 (b) 0.348
(c) 0.192 (d) 0.096

A.1. (c)

Explanation:

Q.2. A slab of a material of refractive index 2.0 shown in figure, has a curved surface APB of radius of curvature 10 cm and a plane surface CD. On the left of APB is air and on the right of CD is water with refractive indices as given in the figure. An object O is placed at a distance of 15 cm from the pole P as shown. The distance of the final image of O from P, as viewed from the left is

(a) 10 cm (b) 20 cm
(c) –30 cm (d) –20 cm

A.2. (c)

Explanation:

Q.3. When a light of wavelength 4000 Å in vacuum travels through the same thickness in diamond and water separately, the difference in the number of waves is 200. Find the thickness, if refractive indices of diamond and water are 5/2 and 4/3 respectively.
(a) 0.685 mm (b) 0.0685 mm
(c) 68.5 mm (d) 6.85 mm

A.3. (b)

Explanation:

Q.4. A beam of natural light falls on a system of 5 polaroids, which are arranged in succession such that the pass axis of each polaroid is turned through 60° with respect to the preceding one. The fraction of the incident light intensity that passes through the system is
(a) 1/64 (b) 1/32 (c) 1/256 (d) 1/512

A.4. (d)

Explanation:

Answer 4

Q.5. A parallel plate capacitor with plate area A and separation between the plates d, is charged by a constant current I. Consider a plane surface of area A/2 parallel to the plates and drawn between the plates. The displacement current through the area is
(a) I (b) I/2 (c) I/4 (d) I/8

A.5. (b)

Explanation:

Q.6. A capacitor made of two circular plates each of radius 12 cm and separated by 5 mm. The capacitor is being charged by an external source. The charging current is constant and equal to 0.15 A. The capacitance and displacement current of the parallel plate capacitor are

(a) 40 pF, 20 A (b) 45 pF, 7.5 A
(c) 70 pF, 35 A (d) 80 pF, 0.075 A

A.6. (d)

Explanation:

Q.7. Two stars are 10 light years away from the earth. They are seen through a telescope of objective diameter 30 cm. The wavelength of light is 600 nm. To see the stars just resolved by the telescope, the minimum distance between them should be (1 light year = 9.46 × 1015 m) of the order of
(a) 108 km (b) 1010 km
(c) 1011 km (d) 106 km

A.7. (a)

Explanation:

Q.8. Electromagnetic wave consists of periodically oscillating electric and magnetic vectors
(a) in mutually perpendicular planes but vibrating with a phase difference of π
(b) in mutually perpendicular planes but vibrating with a phase difference of π/2
(c) in randomly oriented planes but vibrating in phase
(d) in mutually perpendicular planes but vibrating in phase

A.8. (d)

Explanation:

Electromagnetic wave consists of periodically oscillating electric and magnetic vectors in mutually perpendicular planes but vibrating in phase.

Q.9. An object was placed upright 25 cm in front of a converging lens with a focal length of 20 cm. A concave mirror with a focal length of 15 cm was placed 120 cm behind the lens. Which of these describes the final image?
(a) real, enlarged (b) virtual, upright
(c) virtual, inverted (d) inverted, diminished

A.9. (a)

Explanation:

 

 

 

 

 

 

 

 

 

 

 

 

Final magnification = (–4) × (–3) × (–1/2) = –6
Final image is real, inverted and enlarged.

Q.10. A hemispherical glass body of radius 10 cm and refractive index 1.5 is silvered on its curved surface. A small air bubble is 6 cm below the flat surface inside it along the axis. The position of the image of the air bubble made by the mirror is seen

(a) 14 cm below flat surface
(b) 20 cm below flat surface
(c) 16 cm below flat surface
(d) 30 cm below flat surface

A.10. (b)

Explanation:

Q.11. The figure shows the initial position of a point source of light S, a detector D and a lens L. Now at t = 0, all the three start moving towards right with different velocities as shown. The time(s) at which the detector receives the maximum light is


(a) 0.56 s and 8.94 s (b) 3.8 s
(c) 8.94 s and 19.62 s (d) 0.56 s

A.11. (a)

Explanation:

Q.12. When the frequency of the light used is changed from 4 × 1014 s –1 to 5 × 1014 s–1, the angular width of the principal (central) maximum in a single slit Fraunhoffer diffraction pattern changes by 0.6 radian. What is the width of the slit (assume that the experiment is performed in vacuum)?
(a) 1.5 × 10–7 m (b) 3 × 10–7 m
(c) 5 × 10–7 m (d) 6 × 10–7 m

A.12. (c)

Explanation:

Best JEE Books Recommended by JEE Toppers

Check out some of the best JEE Books recommended by JEE Toppers

  • NCERT Textbook

One thing that is strongly recommended is that students prepare using NCERT textbooks. Toppers endorse NCERT as the finest book for JEE Main. NCERT is the foundation for these exams since they cover everything and consist of enormous information. Each and every line of NCERT must be clear and embedded in your mind to know the concepts better.

Objective NCERT at Your Fingertips-Maths, Chem, Phy. Combo

NCERT At Your Fingertips

As we mentioned in the point above, each and every line of NCERT is important. NCERT At Your Fingertips is just the book for that purpose as it has over 100 MCQs from every line of NCERT and provides deep learning. It has MCQs pulled out from NCERT, NCERT Exemplar, previous years’ papers, practice papers, and model test papers. The book is a bestseller on every e-commerce platform and has been referred by teachers and lakhs of JEE toppers and aspirants as a jewel for JEE exam preparation. It has over 8000 5-star ratings and reviews on amazon alone. You can’t miss out on this book for extensive knowledge.

JEE Main Guide

This series has separate books for physics, chemistry, and mathematics. MTG JEE Main Physics is the best book for JEE Main exam based on the latest pattern. The book comprises detailed theory with illustrations followed by Self-check MCQs. Chapter-wise MCQs and Numerical Value Questions with Hints and explanations are included for better understanding.

JEE Main Guide

22 years JEE Main

22 Years JEE Main

Imagine having 21 years’ worth of experience for JEE Main? That is what you’ll get with this series of Physics, chemistry, and mathematics books. MTG’s 22 Years JEE Main Chapter-wise Topic-wise Solutions Physics is the best question bank having questions from the past 22 years of JEE Main Physics (2022-2013) & AIEEE (2012-2002) which are segregated Chapter-wise Topic-wise.

NTA JEE Main

This book for excelling in JEE MAIN has the real 104 online papers by NTA from 2019 to 2023. The book also provides 5 Mock test papers as per the latest pattern of JEE Main exam set by NTA in the end. MCQs and Numerical type questions are present in the book along with chapter-wise graphical analysis indicating the weightage of questions and topics.

NTA JEE MAIN PCM COMBO 2024

JEE Champion Combo-Phy, Chem and Maths

JEE Champion

JEE Champion is a book designed for JEE aspirants to prepare better with the knowledge of topic importance within a chapter. It familiarizes all the JEE aspirants with a wide variety of questions frequently asked in various engineering entrance exams. It covers 10 years of questions for all the major engineering exams. Students can understand the changing pattern of questions asked and can gain mastery over questions asked during exams.

46 Years JEE Advanced

• 46 years of IIT-JEE/ JEE Advanced previous year questions
• Provides a chapter-wise format
• Covers a large question typology
• Covers the entire Class 11th & 12th syllabus
• Fully solved book with detailed explanations
• Provides oldest IIT-JEE exam papers

46 Years JEE Advance

46+22 Years Chapterwise Topicwise Sol. (Phy, Chem, Math) COMBO for JEE

46+22 Years Chapterwise Topicwise Solutions

• 46 Previous Years’ Papers of JEE Advanced/IIT JEE
• All Subjective & Objective Previous Years’ Questions
• 22 Previous Years’ Papers of JEE Main/AIEEE
• All Online & Offline Papers
• 5000+ questions in Chapter-wise and Topic-wise format
• Chapter-wise snapshots, and detailed explanations
• Access to free digital replica aka. Smartbook

Leave a Reply

Your email address will not be published. Required fields are marked *

Update on: 21 Nov 2024, 10:38 AM

Finally, the Central Board of Secondary Education (CBSE) released the Class 10 and Class 12 date sheets for board examinations 2024 on 20 November 2024. According to the schedule released by the CBSE board, the Class 12 board examination will begin on February 15 and…...

Update on: 19 Nov 2024, 11:52 AM

The command of the Hindi language as a subject in Class 10 plays a crucial role for students who aim to pursue a career in Humanities with Hindi as the main language. They can become professors, journalists, translators, proofreaders, screenwriters, novelists, voice associates, etc. with…...

Update on: 19 Nov 2024, 11:30 AM

English is one of the important subjects in CBSE Class 12 Board exams. Irrespective of whether you choose Science, Commerce, or Humanities stream after intermediate, English will be a part of all the streams unless you take any other language in the undergraduate program. So,…...

Update on: 16 Nov 2024, 05:00 PM

Science is one of the most important subjects for CBSE Class 10 board exams as a good score opens doors to multiple career opportunities after Class 10 results. The command of science is essential to opting for the science stream in the intermediate. Sample papers…...

Update on: 16 Nov 2024, 03:46 PM

Mathematics is one of the most important subjects for CBSE Class 10 board exams as a good score opens doors to multiple career opportunities after Class 10 results. The command of Mathematics is essential to opt for the science stream in intermediate because Physics and…...

Update on: 16 Nov 2024, 03:30 PM

Mathematics is one of the essential subjects for CBSE Class 10 board exams as a good score opens doors to multiple career opportunities after Class 10 results. The command of mathematics is necessary to opt for the science stream in intermediate because physics and mathematics…...

Update on: 16 Nov 2024, 10:00 AM

Social Science is often considered an irrelevant subject by aspiring Science and Commerce stream students. However, they must realize that Social Science can play an important role in scoring full marks in CBSE Class 10 Board exams and help them choose the stream of their…...

Update on: 14 Nov 2024, 10:00 AM

English is one of the important subjects in CBSE Class 10 Board exams. Irrespective of whether you choose Science, Commerce, or Humanities stream after matriculation, English will be a part of all the streams unless you take any other language in intermediate. So, students should…...

Update on: 30 Oct 2024, 02:43 PM

Imagine you are in an exam center and the last five minutes remain of the paper and you still have 5-7 questions to solve. You know the answers to all the questions but are not able to decide which one to prioritize due to the…...

Update on: 30 Oct 2024, 02:40 PM

In recent years, the analytical paragraphs have become quite significant in Class 10 board exams. As they hold good weightage in board exams, students must learn to ace analytical paragraphs. Writing an analytical paragraph is a crucial skill that requires certain sets of skills and…...