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Class 9 Science Case Study Questions PDF Download

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Class 9 Science Case Study Questions play a crucial role in the field of science education as they provide real-life scenarios for students to analyze, apply their knowledge, and develop problem-solving skills. This article aims to present a comprehensive collection of case study questions for Class 9 Science , covering various topics and concepts.

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CBSE Class 9 Science Exam will have a set of questions based on case studies in the form of MCQs. The CBSE Class 9 Science Question Bank on Case Studies, provided in this article, can be very helpful to understand the new format of questions. Share this link with your friends.

If you want to want to prepare all the tough, tricky & difficult questions for your upcoming exams, this is where you should hang out.  CBSE Case Study Questions for Class 9  will provide you with detailed, latest, comprehensive & confidence-inspiring solutions to the maximum number of Case Study Questions covering all the topics from your  NCERT Text Books !

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CBSE Class 9th SCIENCE Chapterwise Case Study Question & Solution

Case study questions provide students with real-life scenarios that require critical thinking and application of scientific concepts. They help students understand the practical application of scientific principles and develop problem-solving skills in various scientific disciplines.

Chapterwise Case Study Questions for Class 9 Science

Inboard exams, students will find the questions based on assertion and reasoning. Also, there will be a few questions based on case studies. In that, a paragraph will be given, and then the MCQ questions based on it will be asked. For Science subjects, there would be 5 case-based sub-part questions, wherein a student has to attempt 4 sub-part questions.

• Case Study Questions for Chapter 1 Matter in Our Surroundings
• Case Study Questions for Chapter 2 Is Matter Around Us Pure?
• Case Study Questions for Chapter 3 Atoms and Molecules
• Case Study Questions for Chapter 4 Structure of Atom
• Case Study Questions for Chapter 5 The Fundamental Unit of Life
• Case Study Questions for Chapter 6 Tissues
• Case Study Questions for Chapter 7 Diversity in Living Organisms
• Case Study Questions for Chapter 8 Motion
• Case Study Questions for Chapter 9 Force and Laws of Motion
• Case Study Questions for Chapter 10 Gravitation
• Case Study Questions for Chapter 11 Work and Energy
• Case Study Questions for Chapter 12 Sound
• Case Study Questions for Chapter 13 Why do we Fall ill
• Case Study Questions for Chapter 14 Natural Resources
• Case Study Questions for Chapter 15 Improvement in Food Resources

The above  Case studies for Class 9 Science  will help you to boost your scores as Case Study questions have been coming in your examinations. These CBSE Class 9 Science Case Studies have been developed by experienced teachers of schools.studyrate.in for the benefit of Class 10 students.

Class 9 Maths Case Study Questions

Benefits of Case Studies in Science Education

Case studies offer several advantages over traditional teaching methods. Here are some key benefits:

• Real-World Application : Case studies present authentic scenarios, enabling students to understand how scientific concepts are applied in real-life situations.
• Critical Thinking : Analyzing case studies requires students to think critically, make connections, and apply scientific knowledge to solve problems.
• Interdisciplinary Approach : Case studies often involve multiple scientific disciplines, fostering an interdisciplinary understanding of complex issues.
• Engagement and Active Learning : Case studies actively engage students in the learning process, promoting active participation, discussion, and collaboration.
• Skill Development : Case studies develop essential skills such as analytical thinking, problem-solving, and effective communication of scientific concepts.

Importance of Practicing Case Study Questions

Practicing case study questions is crucial for Class 9 Science students to enhance their understanding and application of scientific concepts. Here’s why it is important:

• Application of Knowledge : Case studies allow students to apply their theoretical knowledge to practical situations, bridging the gap between theory and real-world scenarios.
• Developing Analytical Skills : Analyzing case studies improves students’ ability to identify relevant information, make connections, and draw logical conclusions.
• Problem-Solving Skills : Case studies present complex problems that require students to think critically and develop effective problem-solving strategies.
• Enhanced Exam Performance : Practicing case study questions familiarizes students with the format and types of questions they may encounter in exams, leading to improved performance.

Subjects Covered in the Case Study Questions for Class 9 Science

The case study questions for Class 9 Science cover the following subjects:

• Motion and Forces
• Light and Reflection
• Electricity
• Matter and Its Properties
• Atoms and Molecules
• Structure of the Atom
• Chemical Reactions
• Cell: The Fundamental Unit of Life
• Diversity in Living Organisms
• Natural Resources

Tips for Approaching Case Study Questions

To tackle case study questions effectively, consider the following tips:

• Read Carefully : Pay close attention to the details provided in the case study, as they hold crucial information for solving the problem.
• Analyze Methodically : Break down the problem into smaller components and analyze each part systematically.
• Apply Relevant Concepts : Identify the scientific principles relevant to the case study and apply them appropriately.
• Consider Multiple Perspectives : Explore different angles and viewpoints while proposing solutions, taking into account various scientific factors.
• Provide Justifications : Support your answers with scientific explanations and logical reasoning to strengthen your responses.

The Class 9 Science Case Study Questions provided in this article serve as a valuable resource for students seeking to enhance their scientific knowledge and problem-solving skills. By practicing these case studies, students can develop a deeper understanding of scientific concepts and their practical applications. Embrace this opportunity to engage with real-world scenarios and strengthen your scientific acumen.

Q1: Are the Class 9 Science Case Study Questions aligned with the official curriculum?

Yes, the Class 9 Science Case Study Questions presented in this article are aligned with the official curriculum. They cover relevant topics and concepts that students need to study for their exams.

Q2: Can practicing case study questions alone guarantee success in Class 9 Science exams?

Practicing case study questions is an important part of exam preparation, but it should be complemented with a thorough understanding of the subject matter. It is advisable to study the concepts in detail, refer to textbooks, and engage in other learning activities to achieve success in exams.

Q3: Where I Can get Class 9 Science Case Study Questions ?

You can practice Class 9 Science Case Study Questions on schools.studyrate.in for free.

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Class 9 Science Case Study Questions

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myCBSEguide App

Download the app to get CBSE Sample Papers 2023-24, NCERT Solutions (Revised), Most Important Questions, Previous Year Question Bank, Mock Tests, and Detailed Notes.

If you are wondering how to solve class 9 science case study questions, then myCBSEguide is the best platform to choose. With the help of our well-trained and experienced faculty, we provide solved examples and detailed explanations for the recently added Class 9 Science case study questions.

You can find a wide range of solved case studies on myCBSEguide, covering various topics and concepts. Class 9 Science case studies are designed to help you understand the application of various concepts in real-life situations.

The rationale behind Science

Science is crucial for Class 9 students’ cognitive, emotional, and psychomotor development. It encourages curiosity, inventiveness, objectivity, and aesthetic sense.

In the upper primary stage, students should be given a variety of opportunities to engage with scientific processes such as observing, recording observations, drawing, tabulating, plotting graphs, and so on, whereas in the secondary stage, abstraction and quantitative reasoning should take a more prominent role in science teaching and learning. As a result, the concept of atoms and molecules as matter’s building units, as well as Newton’s law of gravitation, emerges.

Science is important because it allows Class 9 Science students to understand the world around us. It helps to find out how things work and to find solutions to problems at the Class 9 Science level. Science is also a source of enjoyment for many people. It can be a hobby, a career, or a source of intellectual stimulation.

Case study questions in Class 9 Science

The inclusion of case study questions in Class 9 science CBSE is a great way to engage students in critical thinking and problem-solving. By working through real-world scenarios, Class 9 Science students will be better prepared to tackle challenges they may face in their future studies and careers. Class 9 Science Case study questions also promote higher-order thinking skills, such as analysis and synthesis. In addition, case study questions can help to foster creativity and innovation in students. As per the recent pattern of the Class 9 Science examination, a few questions based on case studies/passages will be included in the CBSE Class 9 Science Paper. There will be a paragraph presented, followed by questions based on it.

Examples of Class 9 science class case study questions

Class 9 science case study questions have been prepared by myCBSEguide’s qualified teachers. Class 9 case study questions are meant to evaluate students’ knowledge and comprehension of the material. They are not intended to be difficult, but they will require you to think critically about the material. We hope you find Class 9 science case study questions beneficial and that they assist you in your exam preparation.

The following are a few examples of Class 9 science case study questions.

Class 9 science case study question 1

• due to its high compressibility
• large volumes of a gas can be compressed into a small cylinder
• transported easily
• all of these
• shape, volume
• volume, shape
• shape, size
• size, shape
• the presence of dissolved carbon dioxide in water
• the presence of dissolved oxygen in the water
• the presence of dissolved Nitrogen in the water
• liquid particles move freely
• liquid have greater space between each other
• both (a) and (b)
• none of these
• Only gases behave like fluids
• Gases and solids behave like fluids
• Gases and liquids behave like fluids
• Only liquids are fluids

Answer Key:

• (d) all of these
• (a) shape, volume
• (b) the presence of dissolved oxygen in the water
• (c) both (a) and (b)
• (c) Gases and liquids behave like fluids

Class 9 science case study question 2

• 12/32 times
• 18 g of O 2
• 18 g of CO 2
• 18 g of CH 4
• 1 g of CO 2
• 1 g of CH 4 CH 4
• 2 moles of H2O
• 20 moles of water
• 6.022  ×  1023 molecules of water
• 1.2044  ×  1025 molecules of water
• (I) and (IV)
• (II) and (III)
• (II) and (IV)
• Sulphate molecule
• Ozone molecule
• Phosphorus molecule
• Methane molecule
• (c) 8/3 times
• (d) 18g of CH ​​​​​4
• (c) 1g of H ​​​​​​2
• (d) (II) and (IV)
• (c) phosphorus molecule

Class 9 science case study question 3

• collenchyma
• chlorenchyma
• It performs photosynthesis
• It helps the aquatic plant to float
• It provides mechanical support
• Sclerenchyma
• Collenchyma
• Epithelial tissue
• Parenchyma tissues have intercellular spaces.
• Collenchymatous tissues are irregularly thickened at corners.
• Apical and intercalary meristems are permanent tissues.
• Meristematic tissues, in its early stage, lack vacuoles, muscles
• (I) and (II)
• (III) and (I)
• Transpiration
• Provides mechanical support
• Provides strength to the plant parts
• None of these
• (a) Collenchyma
• (b) help aquatic plant to float
• (b) Sclerenchyma
• (d) Only (III)
• (c) provide strength to plant parts

Cracking Class 9 Science Case Study Questions

There is no one definitive answer to Class 9 Science case study questions. Every case study is unique and will necessitate a unique strategy. There are, nevertheless, certain general guidelines to follow while answering case study questions.

• To begin, double-check that you understand the Class 9 science case study questions. Make sure you understand what is being asked by reading it carefully. If you’re unclear, seek clarification from your teacher or tutor.
• It’s critical to read the Class 9 Science case study material thoroughly once you’ve grasped the question. This will provide you with a thorough understanding of the problem as well as the various potential solutions.
• Brainstorming potential solutions with classmates or other students might also be beneficial. This might provide you with multiple viewpoints on the situation and assist you in determining the best solution.
• Finally, make sure your answer is presented simply and concisely. Make sure you clarify your rationale and back up your claim with evidence.

A look at the Class 9 Science Syllabus

The CBSE class 9 science syllabus provides a strong foundation for students who want to pursue a career in science. The topics are chosen in such a way that they build on the concepts learned in the previous classes and provide a strong foundation for further studies in science. The table below lists the topics covered in the Class 9 Science syllabus of the Central Board of Secondary Education (CBSE). As can be seen, the Class 9 science syllabus is divided into three sections: Physics, Chemistry and Biology. Each section contains a number of topics that Class 9 science students must study during the course.

CBSE Class 9 Science (Code No. 086)

Theme: Materials Unit I: Matter-Nature and Behaviour Definition of matter; solid, liquid and gas; characteristics – shape, volume, density; change of state-melting (absorption of heat), freezing, evaporation (cooling by evaporation), condensation, sublimation. Nature of matter:  Elements, compounds and mixtures. Heterogeneous and homogenous mixtures, colloids and suspensions. Particle nature and their basic units:  Atoms and molecules, Law of constant proportions, Atomic and molecular masses. Mole concept: Relationship of mole to mass of the particles and numbers. Structure of atoms:  Electrons, protons and neutrons, valency, the chemical formula of common compounds. Isotopes and Isobars.

Theme: The World of the Living Unit II: Organization in the Living World Cell – Basic Unit of life:  Cell as a basic unit of life; prokaryotic and eukaryotic cells, multicellular organisms; cell membrane and cell wall, cell organelles and cell inclusions; chloroplast, mitochondria, vacuoles, endoplasmic reticulum, Golgi apparatus; nucleus, chromosomes – basic structure, number. Tissues, Organs, Organ System, Organism: Structure and functions of animal and plant tissues (only four types of tissues in animals; Meristematic and Permanent tissues in plants).

Theme: Moving Things, People and Ideas Unit III: Motion, Force and Work Motion:  Distance and displacement, velocity; uniform and non-uniform motion along a straight line; acceleration, distance-time and velocity-time graphs for uniform motion and uniformly accelerated motion, derivation of equations of motion by graphical method; elementary idea of uniform circular motion. Force and Newton’s laws:  Force and Motion, Newton’s Laws of Motion, Action and Reaction forces, Inertia of a body, Inertia and mass, Momentum, Force and Acceleration. Elementary idea of conservation of Momentum. Gravitation:  Gravitation; Universal Law of Gravitation, Force of Gravitation of the earth (gravity), Acceleration due to Gravity; Mass and Weight; Free fall. Floatation:  Thrust and Pressure. Archimedes’ Principle; Buoyancy. Work, energy and power:  Work done by a Force, Energy, power; Kinetic and Potential energy; Law of conservation of energy. Sound:  Nature of sound and its propagation in various media, speed of sound, range of hearing in humans; ultrasound; reflection of sound; echo.

Theme: Food Unit IV: Food Production Plant and animal breeding and selection for quality improvement and management; Use of fertilizers and manures; Protection from pests and diseases; Organic farming.

PRESCRIBED BOOKS:

• Science-Textbook for class IX-NCERT Publication
• Assessment of Practical Skills in Science-Class IX – CBSE Publication
• Laboratory Manual-Science-Class IX, NCERT Publication
• Exemplar Problems Class IX – NCERT Publication

myCBSEguide: A true helper

There are numerous advantages to using myCBSEguide to achieve the highest results in Class 9 Science.

• myCBSEguide offers high-quality study materials that cover all of the topics in the Class 9 Science curriculum.
• myCBSEguide provides practice questions and mock examinations to assist students in the best possible preparation for their exams.
• On our myCBSEguide app, you’ll find a variety of solved Class 9 Science case study questions covering a variety of topics and concepts. These case studies are intended to help you understand how certain principles are applied in real-world settings
• myCBSEguide is that the study material and practice problems are developed by a team of specialists who are always accessible to assist students with any questions they may have. As a result, students may be confident that they will receive the finest possible assistance and support when studying for their exams.

So, if you’re seeking the most effective strategy to study for your Class 9 Science examinations, myCBSEguide is the place to go!

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Case Study Questions of Class 9 Science PDF Download

Download PDF Case Study Questions of Class 9 Science to prepare for the upcoming CBSE Class 9 Exams Exam 2023-24. With the help of our well-trained and experienced faculty, we provide solved examples and detailed explanations for the recently added  Class 9 Science case study questions .

Case study questions are based on real or hypothetical scenarios that require students to analyze, evaluate, and apply scientific concepts to solve problems or make informed decisions. They often present a detailed context, providing students with the opportunity to demonstrate their understanding of the subject matter beyond basic recall.

Table of Contents

Class 9 Science: Case Study Questions

The inclusion of case study questions in Class 9 science CBSE is a great way to engage students in critical thinking and problem-solving. By working through real-world scenarios, Class 9 Science students will be better prepared to tackle challenges they may face in their future studies and careers. Class 9 Science Case study questions also promote higher-order thinking skills, such as analysis and synthesis. In addition, case study questions can help to foster creativity and innovation in students. As per the recent pattern of the Class 9 Science examination, a few questions based on case studies/passages will be included in the CBSE Class 9 Science Paper. There will be a paragraph presented, followed by questions based on it.

Chapterwise Case Study Questions of Class 9 Science

• Case Study Questions for Chapter 1 Matter in Our Surroundings
• Case Study Questions for Chapter 2 Is Matter Around Us Pure?
• Case Study Questions for Chapter 3 Atoms and Molecules
• Case Study Questions for Chapter 4 Structure of Atom
• Case Study Questions for Chapter 5 The Fundamental Unit of Life
• Case Study Questions for Chapter 6 Tissues
• Case Study Questions for Chapter 7 Diversity in Living Organisms
• Case Study Questions for Chapter 8 Motion
• Case Study Questions for Chapter 9 Force and Laws of Motion
• Case Study Questions for Chapter 10 Gravitation
• Case Study Questions for Chapter 11 Work and Energy
• Case Study Questions for Chapter 12 Sound
• Case Study Questions for Chapter 13 Why do we Fall ill
• Case Study Questions for Chapter 14 Natural Resources
• Case Study Questions for Chapter 15 Improvement in Food Resources

You can find a wide range of solved case studies on cbseexperts, covering various topics and concepts. Class 9 Science case studies are designed to help you understand the application of various concepts in real-life situations.

Class 9 Science Syllabus

Unit I: Matter-Nature and Behaviour

 Definition of matter; solid, liquid, and gas; characteristics – shape, volume, density; change of statementing (absorption of heat), freezing, evaporation (cooling by evaporation), condensation, sublimation.

Nature of matter:  Elements, compounds, and mixtures. Heterogeneous and homogenous mixtures, colloids, and suspensions. Physical and chemical changes (excluding separating the components of a mixture).

Particle nature and their basic units:  Atoms and molecules, Law of Chemical Combination, Chemical formula of common compounds, Atomic and molecular masses.

Structure of atoms:  Electrons, protons and neutrons, Valency, Atomic Number and Mass Number, Isotopes and Isobars.

Unit II: Organization in the Living World

Cell – Basic Unit of life:  Cell as a basic unit of life; prokaryotic and eukaryotic cells, multicellular organisms; cell membrane and cell wall, cell organelles and cell inclusions; chloroplast, mitochondria, vacuoles, endoplasmic reticulum, Golgi apparatus; nucleus, chromosomes – basic structure, number.

Tissues, Organs, Organ System, Organism:  Structure and functions of animal and plant tissues (only four types of tissues in animals; Meristematic and Permanent tissues in plants).

Unit III: Motio n, Force,  and Work

Motion:  Distance and displacement, velocity; uniform and non-uniform motion along a straight line; acceleration, distance-time and velocity-time graphs for uniform motion and uniformly accelerated motion, elementary idea of uniform circular motion.

Force and Newton’s laws:  Force and Motion, Newton’s Laws of Motion, Action and Reaction forces, Inertia of a body, Inertia and mass, Momentum, Force and Acceleration.

Gravitation:  Gravitation; Universal Law of Gravitation, Force of Gravitation of the earth (gravity), Acceleration due to Gravity; Mass and Weight; Free fall. Floatation: Thrust and Pressure. Archimedes’ Principle; Buoyancy.

Work, Energy and Power:  Work done by a Force, Energy, power; Kinetic and Potential energy; Law of conservation of energy (excluding commercial unit of Energy).

Sound: Nature of sound and its propagation in various media, speed of sound, range of hearing in humans; ultrasound; reflection of sound; echo.

Unit IV: Food Production

Plant and animal breeding and selection for quality improvement and management; Use of fertilizers and manures; Protection from pests and diseases; Organic farming.

Books for Class 9 Science Exams

Benefits of Case Study Questions

• Enhancing Analytical Skills : Case study questions challenge students to analyze complex scenarios, identify relevant information, and derive meaningful insights. By engaging with these questions, students develop critical analytical skills that are essential for scientific thinking and problem-solving.
• Promoting Critical Thinking : Case study questions encourage students to think critically and evaluate different perspectives. They require students to reason, make logical deductions, and justify their answers with supporting evidence. This process helps in honing their critical thinking abilities, enabling them to approach problems from multiple angles.
• Encouraging Practical Application of Concepts : By presenting real-world or hypothetical situations, case study questions promote the application of scientific concepts in practical scenarios. This application-based approach fosters a deeper understanding of the subject matter and helps students see the relevance of what they learn in the classroom to everyday life.

Case study questions of Class 9 Science provide students with an opportunity to apply their knowledge, enhance analytical skills, and think critically. By understanding the format, benefits, and effective strategies for answering case study questions, students can excel in this form of assessment. While challenges may arise, practicing time management, improving information extraction skills, and enhancing observation abilities will enable students to overcome these obstacles and perform well. Embracing case study questions as a valuable learning tool can contribute to a holistic understanding of scientific concepts and foster problem-solving abilities.

1. What is the purpose of case study questions in Class 9 Science?

Case study questions serve the purpose of evaluating a student’s understanding of scientific concepts, their ability to apply knowledge in real-life situations, and their analytical and critical thinking skills.

2. How can case study questions help improve analytical skills?

Case study questions require students to analyze complex scenarios, identify relevant information, and derive meaningful insights. Regular practice with such questions can significantly enhance analytical skills.

3. Are case study questions difficult to answer?

Case study questions can be challenging due to their comprehensive nature and the need for critical thinking. However, with practice and effective strategies, students can develop the skills necessary to answer them effectively.

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CBSE Class 9 Science Important Case Study Questions with Answers for Term 2 Exam 2022 (PDF)

Check important case study questions of cbse class 9 science to prepare for the cbse term 2 exam 2022. all these questions have been put together by subject experts..

CBSE Class 9 Term 2 Exam 2022:  Important case based questions for CBSE Class 9 Science are provided here students to prepare for the upcoming Term 2 Exam 2022. All the questions provided below are curated by the subject experts. These questions are really helpful to revise important concepts and prepare the case study questions for the exam. Answers to all questions have been provided for reference. So, students should practice the chapter-wise questions to clearly understand the right way to attempt the case based questions. Download the chapter-wise questions in PDF.

Check some of the important case study questions below:

Q. Read the following and answer the questions :

A student was asked by his teacher to verify the law of conservation of mass in the laboratory. He prepared 5% aqueous solutions of NaCl and Na 2 SO 4 . He mixed 10 mL of both these solutions in a conical flask. He weighed the flask on a balance. He then stirred the flask with a rod and weighed it after sometime. There was no change in mass.

• Was the student able to verify the law of conservation of mass?
• If not, what was the mistake committed by him?
• In your opinion, what he should have done?
• What is the molar mass of Na 2 SO 4 ?
• No, he could not verify the law of conservation of mass in-spite of the fact that there was no change in mass.
• No chemical reaction takes place between NaCl and Na 2 SO 4 . This means that no reaction actually took place in the flask.
• He should have performed the experiment by using aqueous solutions of BaCl 2 and Na 2 SO 4 . A chemical reaction takes place in this case and a white precipitate of BaSO 4 is formed.
• Will the weight of the precipitate be the same as that of the reactants before mixing?
• If not, what she should have done?
• Which law of chemical combination does this support?
• State the law of conservation of mass.
• No, it will not be the same.
• She should have weighed the total contents of the beaker after the reaction and not the precipitate alone.
• It supports the law of conservation of mass.
• Mass can neither be created nor destroyed during a chemical reaction.

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CBSE Case Study Questions for Class 9 Science - Pdf PDF Download

Cbse case study questions for class 9 science.

Case based questions for Class 9 Science involve exploring a real-world situation through scientific analysis and inquiry. These questions allow students to make connections between science concepts and the world around them, as well as develop critical thinking skills. For example, a case study may involve challenging a student to determine the cause of an illness in a local population by researching the disease, its symptoms, and the local environment. Through this exercise, students learn how to identify a problem, break it down into parts, and come up with a solution that is supported by evidence. This type of question helps students to understand how science is at the centre of solving real-world problems.

Chapter Wise Case Based Questions for Class 9 Science

Chapter-wise case-based questions for Class 9 Science are a set of questions based on specific chapters or topics covered in the science textbook. These questions are designed to help students apply their understanding of scientific concepts to real-world situations and events.

The CBSE Class 9 Case Based Questions can be accessed from Chapetrwise Links provided below:

Chapter 1: Matter In Our Surroundings

Chapter 2: is matter around us pure.

• Case Based Questions: Is Matter Around Us Pure?

Chapter 3: Atoms And Molecules

• Case Based Questions: Atoms And Molecules

Chapter 4: Structure Of The Atom

• Case Based Questions: Structure Of The Atom

Chapter 5: The Fundamental Unit Of Life

• Case Based Questions: The Fundamental Unit Of Life- 1
• Case Based Questions: The Fundamental Unit Of Life- 2

Chapter 6: Tissues

• Case Based Questions: Tissues- 1
• Case Based Questions: Tissues- 2

Chapter 7: Motion

• Case Based Questions: Motion-1 
• Case Based Questions: Motion- 2

Chapter 8: Force And Laws Of Motion

• Case Based Questions: Force And Laws Of Motion

Chapter 9: Gravitation

• Case Based Questions: Gravitation

Chapter 10: Work And Energy

• Case Based Questions: Work And Energy- 1
• Case Based Questions: Work And Energy- 2

Chapter 11: Diversity In Living Organisms

Chapter 12: sound, chapter 13: natural resources, chapter 14: improvement in food resource, chapter 15: why do we fall ill.

• Case Based Questions: Why Do We Fall Ill?

Weightage of Case Based Questions in Class 9 Science

Why are Case Study Questions important in Science Class  9?

• Enhance critical thinking:  Case study questions require students to analyze a real-life scenario and think critically to identify the problem and come up with possible solutions. This enhances their critical thinking and problem-solving skills.
• Apply theoretical concepts:  Case study questions allow students to apply theoretical concepts that they have learned in the classroom to real-life situations. This helps them to understand the practical application of the concepts and reinforces their learning.
• Develop decision-making skills:  Case study questions challenge students to make decisions based on the information provided in the scenario. This helps them to develop their decision-making skills and learn how to make informed decisions.
• Improve communication skills:  Case study questions often require students to present their findings and recommendations in written or oral form. This helps them to improve their communication skills and learn how to present their ideas effectively.
• Enhance teamwork skills:  Case study questions can also be done in groups, which helps students to develop teamwork skills and learn how to work collaboratively to solve problems.

In summary, case study questions are important in Class 9 because they enhance critical thinking, apply theoretical concepts, develop decision-making skills, improve communication skills, and enhance teamwork skills. They provide a practical and engaging way for students to learn and apply their knowledge and skills to real-life situations.

Class 9 Science Curriculum at Glance

The Class 9 Science curriculum in India covers a wide range of topics and concepts. Here is a brief overview of the Science curriculum at a glance:

• Physics:  The Physics section includes topics such as motion, force, work and energy, sound, and light.
• Chemistry:  The Chemistry section includes topics such as matter, atoms and molecules, structure of the atom, and chemical reactions.
• Biology:  The Biology section includes topics such as cell structure and functions, tissues, diversity in living organisms, natural resources, and environmental management.
• Practical Work:  The Science curriculum also includes practical work, where students perform experiments to observe and understand scientific phenomena.

The Class 9 Science curriculum is designed to provide a strong foundation in science and prepare students for higher education in the field. The curriculum is structured to develop critical thinking, problem-solving, and analytical skills, and to promote the application of scientific concepts in real-life situations. The curriculum is also designed to help students prepare for competitive exams and develop a strong scientific base for future academic and professional pursuits.

Students can also access Case Based Questions of all subjects of CBSE Class 9

• Case Based Questions for Class 9 Maths
• Case Based Questions for Class 9 Social Science
• Case Based Questions for Class 9 English
• Case Based Questions for Class 9 Hindi
• Case Based Questions for Class 9 Sanskrit

Frequently Asked Questions (FAQs) on Case Based Questions for Class 9 Science

Are case-based questions on the class 9 science exam.

Yes, case-based questions are often included in science exams at the class 9 level as they test students' ability to apply their scientific knowledge and skills to real-world situations.

How are case-based questions different from traditional science questions?

Traditional science questions typically focus on testing students' knowledge of specific facts, concepts, and theories. Case-based questions, on the other hand, require students to use their knowledge and understanding to analyze and interpret real-world situations and make informed decisions.

How can students prepare for case-based questions in science?

To prepare for case-based questions in science, students should practice analyzing data and interpreting scientific experiments. They should also work on developing their critical thinking and problem-solving skills.

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Class 9th Science - Motion Case Study Questions and Answers 2022 - 2023

By QB365 on 09 Sep, 2022

QB365 provides a detailed and simple solution for every Possible Case Study Questions in Class 9th Science Subject - Motion, CBSE. It will help Students to get more practice questions, Students can Practice these question papers in addition to score best marks.

QB365 - Question Bank Software

Motion case study questions with answer key.

9th Standard CBSE

Final Semester - June 2015

(ii) Find the Velocity of the boy.

(iii) A boy is sitting on a merry-go-round which is moving with a constant speed of 10m/s. This means that the boy is :

(iv) In which of the following cases of motion, the distance moved and the magnitude of displacement are equal ?

(ii) How far does it travel in 1 second ?

(iii) How far does it travel in 6 seconds ?

(iv) How long does it take to travel 240 m ?

(v) Which of the following statement is correct regarding velocity and speed of a moving body? (a) velocity of a moving body is always higher than its speed (b) speed of a moving body is always higher than its velocity (c) speed of a moving body is its velocity in a given direction (d) velocity of a moving body is its speed in a given direction

(ii) What type of motion is represented by BC ?

(iii) Find out the acceleration of the body.

(iv) Calculate the retardation of the body.

(v) Find out the distance travelled by the body from A to B.

*****************************************

Motion case study questions with answer key answer keys.

(i) (b) 2 m/s Total distance travelled is 100 m + 100 m = 200 m and the total time taken is 50 s + 50 s = 100 s. \(\text { Speed of boy }=\frac{\text { Distance travelled }}{\text { Time taken }}=\frac{200 \mathrm{~m}}{100 \mathrm{~s}}=2 \mathrm{~m} / \mathrm{s}\) (ii) (d) 0 m/s The boy runs 100 m towards East and then 100 m towards West and reaches at the starting point, his home. So, the displacement will be 100 m – 100 m = 0 m. The total time taken is 50 s + 50 s = 100 s. \(\text { Velocity of boy }=\frac{\text { Displacement }}{\text { Time taken }}=\frac{0 \mathrm{~m}}{100 \mathrm{~s}}=0 \mathrm{~m} / \mathrm{s}\) (iii) (c) in accelerated motion (iv) (a) if the car is moving on straight road (v) (c) 2r

(i) (b) 30 m/s Average speed = total distance travelled/total time taken = 150/5 = 30 m/s (ii) (b) 30 m Time = 1 s Distance = (average speed)(time) = 30 m/s x 1s = 30 m (iii) (c) 180 m  Time = 6 s Distance = (average speed)(time) = 30 m/s x 6s = 180m (iv) (d) 8s Distance = 240m Time = Distance/average speed = 240/30 = 8s (v) (d) velocity of a moving body is its speed in a given direction

(i) (b) uniform acceleration OA is a straight line graph between speed and time, and it is sloping upwards from O to A. Therefore, the graph line OA represents uniform acceleration. (ii) (c) negative acceleration BC is a straight line graph between speed and time which is sloping downwards from B to C. Therefore, BC represents uniform retardation (or negative acceleration). (iii) (a) 1.5 m/s 2 The slope of speed-time graph OA will give us the acceleration of the body. Thus, Acceleration = Slope of line OA = AD/OD Now, in the given graph, we find that AD = 6 m/s and OD = 4 seconds. So, putting these values in the above relation, we get : Acceleration = 6 m/s / 4 s = 1.5 m/s 2 (iv) (d) 1 m/s 2 The slope of speed-time graph BC will be equal to the retardation of the body. So, Retardation = Slope of line BC = BE/EC Now, in the graph given to us, we find that BE = 6 m/s and EC = 16 – 10 = 6 seconds. So, putting these values in the above relation, we get : Retardation = 6m/s / 6 s = 1 m/s 2 (v) (c) 36 m Distance travelled from A to B = Area under the line AB and the time axis = Area of rectangle DABE = DA × DE Now, from the given graph, we find that DA = 6 m/s and DE = 10 – 4 = 6 s. Therefore, Distance travelled from A to B = 6 × 6 = 36 m

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Case Study Questions for Class 9 Science Chapter 1 Matter in Our Surroundings

• Last modified on: 6 days ago
• Reading Time: 6 Minutes

Here we are providing case study questions for class 9 science chapter 12 sound. Students are suggested to go through each and every case study questions for better understanding of the chapter.

Case Study/Passage Based Questions:

Question 1:

Read the following passage and answer the questions given below.

Every matter is made up of tiny particles. These particles are so tiny that they can’t be seen with naked eyes.

The three characteristics shown by particles of matter are as follows:

(i) There are small voids between particles in a matter. This characteristic is the concept behind the solubility of a substance in other substances.

(ii) Particles of matter show continuous random movements, that is they possess kinetic energy. The spreading of ink in a beaker of glass, smell of agarbattis, etc. are few illustrations that show the movement of particles of a substance.

(iii) The particles of matter attract each other with a force called interparticle force of attraction. Read the given passage carefully and give the answer of the following questions:

Q 1. Spreading of fragrance of a burning incense stick in a room shows that:

a. particles of matter have spaces between them.

b. particles of matter attract each other.

c. particles of matter are constantly moving.

d. None of the above

Q 2. What happens when we add sugar to water?

a. Volume of water doubles.

b. Volume of water decreases

c. Volume of water remains the same.

Q 3. A stream of water cannot be cut by fingers. Which property of matter does this observation show?

a. Particles of matter attract each other.

b. Particles of matter have spaces between them.

c. Particles of matter are continuously moving.

Q 4. When we put some crystals of potassium permanganate in a beaker containing water, we observe that after some time, the whole water turns pink. This intermixing of particles of two different types of matter on their own is called:

a. Brownian motion

c. sublimation

d. diffusion

Q 5. Why is the rate of diffusion of liquids higher than that of solids?

a. In the liquid state, particles are tightly packed as compared to solids.

b. In the liquid state, particles move freely as compared to solids.

c. In solid state, particles have least force of attraction between the particles.

d. In solid state, particles cannot be compressed easily.

• (c) particles of matter are constantly moving.
• (c) Volume of water remains the same.
• (a) Particles of matter attract each other.
• (d) diffusion
• (b) In the liquid state, particles move freely as compared to solids

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Prestigious cancer research institute has retracted 7 studies amid controversy over errors

Seven studies from researchers at the prestigious Dana-Farber Cancer Institute have been retracted over the last two months after a scientist blogger alleged that images used in them had been manipulated or duplicated.

The retractions are the latest development in a monthslong controversy around research at the Boston-based institute, which is a teaching affiliate of Harvard Medical School. 

The issue came to light after Sholto David, a microbiologist and volunteer science sleuth based in Wales, published a scathing post on his blog in January, alleging errors and manipulations of images across dozens of papers produced primarily by Dana-Farber researchers . The institute acknowledged errors and subsequently announced that it had requested six studies to be retracted and asked for corrections in 31 more papers. Dana-Farber also said, however, that a review process for errors had been underway before David’s post. 

Now, at least one more study has been retracted than Dana-Farber initially indicated, and David said he has discovered an additional 30 studies from authors affiliated with the institute that he believes contain errors or image manipulations and therefore deserve scrutiny.

The episode has imperiled the reputation of a major cancer research institute and raised questions about one high-profile researcher there, Kenneth Anderson, who is a senior author on six of the seven retracted studies. 

Anderson is a professor of medicine at Harvard Medical School and the director of the Jerome Lipper Multiple Myeloma Center at Dana-Farber. He did not respond to multiple emails or voicemails requesting comment. 

The retractions and new allegations add to a larger, ongoing debate in science about how to protect scientific integrity and reduce the incentives that could lead to misconduct or unintentional mistakes in research. 

The Dana-Farber Cancer Institute has moved relatively swiftly to seek retractions and corrections. 

“Dana-Farber is deeply committed to a culture of accountability and integrity, and as an academic research and clinical care organization we also prioritize transparency,” Dr. Barrett Rollins, the institute’s integrity research officer, said in a statement. “However, we are bound by federal regulations that apply to all academic medical centers funded by the National Institutes of Health among other federal agencies. Therefore, we cannot share details of internal review processes and will not comment on personnel issues.”

The retracted studies were originally published in two journals: One in the Journal of Immunology and six in Cancer Research. Six of the seven focused on multiple myeloma, a form of cancer that develops in plasma cells. Retraction notices indicate that Anderson agreed to the retractions of the papers he authored.

Elisabeth Bik, a microbiologist and longtime image sleuth, reviewed several of the papers’ retraction statements and scientific images for NBC News and said the errors were serious. 

“The ones I’m looking at all have duplicated elements in the photos, where the photo itself has been manipulated,” she said, adding that these elements were “signs of misconduct.” 

Dr.  John Chute, who directs the division of hematology and cellular therapy at Cedars-Sinai Medical Center and has contributed to studies about multiple myeloma, said the papers were produced by pioneers in the field, including Anderson. 

“These are people I admire and respect,” he said. “Those were all high-impact papers, meaning they’re highly read and highly cited. By definition, they have had a broad impact on the field.” 

Chute said he did not know the authors personally but had followed their work for a long time.

“Those investigators are some of the leading people in the field of myeloma research and they have paved the way in terms of understanding our biology of the disease,” he said. “The papers they publish lead to all kinds of additional work in that direction. People follow those leads and industry pays attention to that stuff and drug development follows.”

The retractions offer additional evidence for what some science sleuths have been saying for years: The more you look for errors or image manipulation, the more you might find, even at the top levels of science. 

Scientific images in papers are typically used to present evidence of an experiment’s results. Commonly, they show cells or mice; other types of images show key findings like western blots — a laboratory method that identifies proteins — or bands of separated DNA molecules in gels. 

Science sleuths sometimes examine these images for irregular patterns that could indicate errors, duplications or manipulations. Some artificial intelligence companies are training computers to spot these kinds of problems, as well. 

Duplicated images could be a sign of sloppy lab work or data practices. Manipulated images — in which a researcher has modified an image heavily with photo editing tools — could indicate that images have been exaggerated, enhanced or altered in an unethical way that could change how other scientists interpret a study’s findings or scientific meaning. 

Top scientists at big research institutions often run sprawling laboratories with lots of junior scientists. Critics of science research and publishing systems allege that a lack of opportunities for young scientists, limited oversight and pressure to publish splashy papers that can advance careers could incentivize misconduct. 

These critics, along with many science sleuths, allege that errors or sloppiness are too common , that research organizations and authors often ignore concerns when they’re identified, and that the path from complaint to correction is sluggish. 

“When you look at the amount of retractions and poor peer review in research today, the question is, what has happened to the quality standards we used to think existed in research?” said Nick Steneck, an emeritus professor at the University of Michigan and an expert on science integrity.

David told NBC News that he had shared some, but not all, of his concerns about additional image issues with Dana-Farber. He added that he had not identified any problems in four of the seven studies that have been retracted. 

“It’s good they’ve picked up stuff that wasn’t in the list,” he said. 

NBC News requested an updated tally of retractions and corrections, but Ellen Berlin, a spokeswoman for Dana-Farber, declined to provide a new list. She said that the numbers could shift and that the institute did not have control over the form, format or timing of corrections. 

“Any tally we give you today might be different tomorrow and will likely be different a week from now or a month from now,” Berlin said. “The point of sharing numbers with the public weeks ago was to make clear to the public that Dana-Farber had taken swift and decisive action with regard to the articles for which a Dana-Farber faculty member was primary author.” 

She added that Dana-Farber was encouraging journals to correct the scientific record as promptly as possible. 

Bik said it was unusual to see a highly regarded U.S. institution have multiple papers retracted. 

“I don’t think I’ve seen many of those,” she said. “In this case, there was a lot of public attention to it and it seems like they’re responding very quickly. It’s unusual, but how it should be.”

Evan Bush is a science reporter for NBC News. He can be reached at [email protected].

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Case Study Questions Class 9 Science Sound

Case study questions class 9 science chapter 12 sound.

CBSE Class 9 Case Study Questions Science Sound. Important Case Study Questions for Class 9 Exam. Here we have arranged some Important Case Base Questions for students who are searching for Paragraph Based Questions Sound.

At Case Study Questions there will given a Paragraph. In where some Questions will made on that respective Case Based Study. There will various types of marks will given 1 marks, 2 marks, 3 marks or 4 marks.

CBSE Case Study Questions Class 9 Science – Sound

(1) Sound is produced by vibrating objects. The matter or substance through which sound is transmitted is called a medium. It can be solid, liquid or gas. Sound moves through a medium from the point of generation to the listener. When an object vibrates, it sets the particles of the medium around it vibrating. The particles do not travel all the way from the vibrating object to the ear. Sound waves are characterized by the motion of particles in the medium and are called mechanical waves.When a vibrating objectmoves forward, it pushes and compresses theair in front of it creating a region of highpressure; this region is called a compression(C).When the vibrating object moves backwards,it creates a region of low pressure calledrarefaction (R). Hence sound is longitudinal wave.

(i) Sound waves are

(a) Mechanical waves

(b) Electromagnetic wave

(c) Transverse waves

(d) None of these

(ii) Sound travel in medium with

(a) Compression and rare fraction

(b) Crest and trough

(c) Both can be possible

(iii) Compression is the region of

(a) High pressure

(b) Low pressure

(c) Medium pressure

(iv) What is sound and how is it produced?

(v) Why sound wave is called as longitudinal wave?

Answer key 1

(iv) Sound is vibrations created by object. When body vibrates, it forces the adjacent particles of the medium to vibrate. This results in disturbance in the medium, which travels as waves an reaches the ear hence sound is produced.

(v) The vibration of medium that travels parallel to direction of wave or along in the direction of the wave is called longitudinal wave. The direction of particles of medium vibrates parallel to direction of propagation of disturbance. Therefore a sound is called longitudinal waves.

(2) The individual particlesof the medium move in a direction parallel tothe direction of propagation of thedisturbance. The particles do not move fromone place to another but they simply oscillateback and forth about their position of rest.This is exactly how a sound wave propagates;hence sound waves are longitudinal waves.There is also another type of wave, calleda transverse wave. In a transverse waveparticles do not oscillate along the direction of wave propagation but oscillate up and downabout their mean position as the wave travels.Thus, a transverse wave is the one in whichthe individual particles of the medium move about their mean positions in a directionperpendicular to the direction of wavepropagation.

(a) Transverse waves

(b) Longitudinal  wave

(c) Both a and b

(ii) Light is

(iii) In case of Longitudinal waves

(a) The particles do not move fromone place to another but they simply oscillateback and forth about their position of rest

(b) The particles move fromone place to another

(c) The particles move up and down.

(iv) When stone is dropped in water; waves are generated of which types?

(v) Differentiate between longitudinal wave and transverse waves.

Answer key-2

(iv) When stone is dropped in water. Waves are generated where water particles are moving up and down and propagated away from dropping point .hence this is sign of transverse waves. Hence transverse waves are produced when stone is dropped in water.

(v) Following are differentiated points

• The distance between two consecutivecompressions (C) or two consecutiverarefactions (R) is called the wavelength.The wavelength is usually represented by λ (Greek letter lambda). Its SI unit is meter (m). • If we can count the number of the compressions or rarefactions that cross us per unit time, we will get the frequency of the sound wave. It is usually represented by υ (Greek letter, nu). SI unit is hertz (symbol, Hz). • The time taken for one complete oscillation is called the time period of the sound wave. It is represented by the symbol T. Its SI unit is second (s).Frequency and time period are related asfollows: υ=1/λ • The speed of sound is defined as the distance which a point on a wave, such as a compression or a rarefaction, travels per unit time.

speed, v = distance / time

v= λ/T = υλ

(i ) SI unit of wavelength

(ii)SI unit of Frequency

(iii) Relation between frequency and time is given by

(a) frequency and time are directly proportional

(b) frequency and time are inversely  proportional

(c) There is no relation between them

(iv) Define speed of sound. Give its formula in terms of wavelength and frequency

(v) Define wavelength frequency and time period of longitudinal wave

answer key-3

(iv) The speed of sound is defined as the distance which a point on a wave, such as a compression or a rarefaction, travels per unit time.

v= λ/T = υλ.

(v) The distance between two consecutive compressions (C) or two consecutive rarefactions (R) is called the wavelength.The wavelength is usually represented by λ (Greek letter lambda). Its SI unit is meter (m).

If we can count the number of the compressions or rarefactions that cross us per unit time, we will get the frequency of the sound wave. It is usually represented by υ (Greek letter, nu). SI unit is hertz (symbol, Hz).

The time taken for one complete oscillation is called the time period of the sound wave. It is represented by the symbol T. Its SI unit is second (s).Frequency and time period are related as follows:  υ= 1/λ.

(4) A violin and a flute may both be played the same time in an orchestra. Bothsounds travel through the same medium,that is, air and arrive at our ear at the sametime. Both sounds travel at the same speedirrespective of the source. But the soundswe receive are different. This is due to thedifferent characteristics associated with thesound. Pitch is one of the characteristics.How the brain interprets the frequency ofan emitted sound is called its pitch. The fasterthe vibration of the source, the higher is the frequency and the higher is the pitch. The magnitude of the maximumdisturbance in the medium on either side ofthe mean value is called the amplitude of thewave. It is usually represented by the letter (A).

The loudness or softness of a sound isdetermined basically by its amplitude. Theamplitude of the sound wave depends uponthe force with which an object is made tovibrate. If we strike a table lightly, we hear asoft sound because we produce a sound waveof less energy (amplitude).

The quality or timber of sound is thatcharacteristic which enables us to distinguishone sound from another having the same pitchand loudness. The sound which is morepleasant is said to be of a rich quality. A sound of single frequency is called a tone. The sound which is produced due to a mixture of several frequencies is called a note and is pleasant to listen to. Noise is unpleasant to the ear! Music is pleasant to hear and is of rich quality.

(i) Pitch of sound is higher when

(a) Vibration of source of sound is higher

(b) Vibration of source of sound is Lower

(c) Independent of vibration of source of sound

(ii) Loudness and softness of sound depends upon

(a) Frequency of sound

(b) Amplitude of sound

(c) Wavelength of sound

(iii) Sound of single frequency is called

(iv)If we strike a table lightly, we hear asoft sound. If we hit the tablehard we hear a louder sound up to large distance. Why?

(v) Determine which of the following has higher pitch railway horn or guitar?

Answer key-4

(iv) If we hit the table hard we hear a louder sound because A sound wave spreads out from its source. As it moves away from the source its amplitude as well as its loudness decreases. Louder sound can travel a larger distance as it is associated with higher energy.

(v) Pitch of sound depends on the frequency of vibration of waves and if the frequency of vibration is higher we say that the sound has higher pitch. Pitch of the sound is the response of our ear. So, basically guitar has 6 strings and the sharpness of each string increases on going below. On the other hand in car horns, there is flat pitch with high noise which can affect anyone’s heart too. As guitar has higher frequency than car horn as number of vibrations per unit time of guitar string are more than car.

(5) Sound bounces off a solid or a liquid like a rubber ball bounces off a wall. Like light, sound

gets reflected at the surface of a solid or liquid and follows the same laws of reflection. The directions in which the sound is incident and is reflected make equal angles with the normal to the reflecting surface at the point of incidence, and the three are in the same plane. If we clap near a suitable reflecting object such as a tall building or a mountain, we will hear the same sound again a little later. This sound which we hear is called an echo. The sensation of sound persists in our brain for about 0.1 s. To hear a distinct echo the time interval between the original sound and the reflected one must be at least 0.1s. Hence, for hearingdistinct echoes, the minimum distance of theobstacle from the source of sound must be 17.2 m. Thisdistance will change with the temperature ofair. Another phenomenon of reflection of sound is reverberation.A sound created in a big hall will persist byrepeated reflection from the walls until it isreduced to a value where it is no longeraudible. The repeated reflection that resultsin this persistence of sound is called reverberation. Excessive reverberation is highly undesirable.

(i) Which of the following is true related to reflection of sound?

(a) Directions in which the sound is incident and is reflected make equal angles with the normal to the reflecting surface at the point of incidence.

(b) Incident wave reflected wave and normal lies in same plane

(c) Both a and b are true.

(ii)For hearing distinct echoes, the minimum distance of the obstacle from the source of sound must be

(iii) Excessive reverberation is 

(a) Desirable phenomenon

(b) Undesirable phenomenon

(c) Does not exist

(iv) A person makes sound near a obstacle and heard the echo after 1 s. What is the distance of the obstacle from the person if the speed of the sound, v is taken as 346 m/s?

(v) State law of reflection of sound.

Answer key-5

(iv) Given,

Speed of sound, v = 346 m/s

Time taken for hearing the echo, t = 1 s

Distance travelled by the sound= v × t = 346 m/s × 1 s = 346 m

In 1 s sound has to travel twice the distance between the obstacle and the person.

Hence, the distance between the obstacle and the person= 346/2 = 173 m.

(v) Law of reflection states that The directions in which the sound is incident and is reflected make equal angles with the normal to the reflecting surface at the point of incidence, and the three  that is reflected wave, incident wave and normal to surface are in the same plane.

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