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Class 9 Science Case Study Questions

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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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Class 9 Physics (India)

Class 9 chemistry (india), class 9 biology (india).

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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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Class 9 Physics Index

Class 9 Physics index given here lists all the topics discussed in class 9 Physics chapters. The listed index is prepared as per the NCERT textbook and the latest CBSE syllabus. Access free study material by clicking on the respective subtopics.

Why is this important?

Before the start of a new academic year, it is helpful to go through the course guide because of the following reasons:

• It gives you an idea of the learning materials, core books, or reference books (if any) that you need for the new session. Knowing this helps you arrange all the required things  in time.
• A clear outline of the topics and learning areas that you will approach throughout the academic year will be presented to you.

Class 9 physics opens doors to fascinating topics such as motion, gravitation, sound, work, power, and more. These topics are very important for students who wish to pursue a career in Physics discipline. Master these concepts and build a strong foundation to improve your expertise on the subject.

Stay tuned with BYJU’S for more such interesting articles. Also, register to “BYJU’S – The Learning App” for loads of interactive, engaging Physics-related videos and an unlimited academic assist.

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NCERT Class 9 Science - Latest Syllabus Based Study Material

Learn class 9 science with our easy-to-follow study material. we've gathered everything a student needs to explore physics, chemistry, biology, and more. our guide breaks down tough science concepts into simple explanations, making learning fun and accessible. perfect for sparking curiosity and building a strong foundation in science..

Important Diagrams

Discover a smoother learning journey through our effortless roadmap

Chapter 1 - Matter in Our Surroundings

Matter is Made of Tiny Particles

States of Matter: Solid, Liquid, Gas and Plasma

Change of State of Matter

Evaporation

Chapter 2 - Is Matter Around Us Pure

Solution: Properties of Solution

Difference Between Physical And Chemical Change

Pure Substance

Chapter 3 - Atoms and Molecules

Laws of Chemical Combination

What is Atom?

Difference Between Atom And Molecule

Chemical Formula

Molecular Mass

Chapter 4 - Structure of the Atom

Charged Particles in Matter

Atomic Structure

Arrangement of Electrons in the Atoms

Relation Between Mass Number and Atomic Number

Chapter 5 - The Fundamental Unit of Life

12 articles

What are Living Organisms Made Up of?

Plasma Membrane - Definition, Structure, Components, Functions

Nucleus: Structure and Function

Cytoplasm - Structure and Function

Endoplasmic Reticulum - Structure, Types And Functions

Golgi Apparatus

Lysosomes - Definition, Types, Significance, Functions

Mitochondria

What are Plastids? - Class 9 Biology

Cell Division: Mitosis & Meiosis, Different Phases of Cell Cycle

Chapter 6 - Tissues

Are Plants and Animals Made of Same Types of Tissues?

Meristematic Tissues - Definition, Features, Types, Role

Structure and Types of Animal Tissues

Permanent Tissues - Diagram, Types Notes Biology Class 9

Epithelial Tissue - Introduction, Characteristics, Types, Importance

Overview and Types of Connective Tissue

Muscular Tissue

Nervous Tissue - Definition, Characteristics, Functions, Types

Chapter 7 - Motion

What is Motion?

Measuring the Rate of Motion

Acceleration

Equation of Motion by Graphical Method

Uniform Circular Motion

Chapter 8 - Force and Laws of Motion

Balanced and Unbalanced Forces

Newton's First Law of Motion

Mass and Inertia

Newton's Second Law of Motion: Definition, Formula, Derivation, and Applications

Newton's Third Law of Motion

Chapter 9 - Gravitation

Gravitational Force

Mass and Weight

What is Pressure?

Archimedes Principle

Chapter 10 - Work and Energy

Work - Definition, Formula, Types of Work, Sample Problems

Chapter 11 - Sound

Production and Propagation of Sound

Reflection of Sound

Chapter 12 - Improvement in Food Resources

13 articles

Improvement in Crop Yields

Crop Variety Improvement

Crop Production and Management

Nutrient Management

What is Manure? Definition, Types, Advantages and Disadvantages

What is Fertilizer? - Example, Definition, Types, and Uses

Irrigation: Meaning, Types, Methods and Importance

Cropping Patterns

Storage of Grains - Overview, Importance, Affecting Factors

What is Animal Husbandry? Definition, Types, Role in Agriculture

Poultry Farming

Inland Fisheries - Overview and Examples

Bee Keeping - Improvement in Food Resources

Important Biology Diagrams - Class 8-12 & NEET

NCERT Soultions for Class 9

NCERT Solutions for Class 9 Science Chapter 5 - The Fundamental Unit Of Life

NCERT Solutions For Class 9 Science Chapter 6 Tissues

NCERT Solutions for Class 9 Science Chapter 12 Improvement in Food Resources

The Class 9 Science Guide is designed to not only cover theoretical aspects but also include practical experiments such as the preparation of solutions, studying cell structure under a microscope, verifying the laws of reflection of sound, and more, to encourage hands-on learning and a deeper understanding of the concepts.

What do we offer?

This GeeksforGeeks NCERT Class 9 Science Study Material for the academic year 2023-24 covering a wide range of topics essential for building a solid foundation in science. Here, you learn all Important Science concepts with clear explanations and visuals.

Key Highlights of this Study Material:

• NCERT-Based Updated Curriculum.
• Clear diagrams of all Science Concepts.
• Allows connectivity to data sources
• Guides for simple experiments.
• Science in everyday life examples.

Your resources are top-notch! They've been instrumental in enhancing my understanding of complex concepts. Kudos to your team for creating such insightful content!

I'm thoroughly impressed by the quality of your materials. They've significantly enriched my learning experience.

Your Class 9 content is exceptional! It's clear, comprehensive, and immensely helpful. The engaging presentation and practical examples make learning enjoyable.

Niraj Chopra

Thank you for providing such valuable resources that greatly enhance students' understanding of Science.

Is this Study Material suitable for all Class 9 students?

This Class 9 Science course is designed for both CBSE and State Board students. It's tailored to support various learning styles, ensuring it covers the full syllabus effectively.

Which chapter is the most important in Class 9 Science?

In Class 9 Science, there isn't one single chapter that stands out as the most important. Each chapter builds on the others to provide a comprehensive foundation in science. It's essential to focus on all chapters to develop a strong understanding of physics, chemistry, and biology.

Which is the best guide for Class 9 NCERT Science?

This guide is sufficient for exam preparation and scoring good marks in your final Class 9th exams. For a more detailed understanding, referring to the NCERT Textbook for Class 9 Science textbooks is recommended.

How can I score full marks in Class 9 Science?

Here are some Tips to Score Above 90% Marks in the Class 9th Science Exam: Grasp the basic concepts across all chapters. Regularly practice with past papers and sample questions. Prioritize topics based on marks distribution. Utilize diagrams and visual aids for better retention. Revise frequently to reinforce learning. Efficient time management during both preparation and exams.

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New evidence found for Planet 9

by Bob Yirka , Phys.org

A small team of planetary scientists from the California Institute of Technology, Université Côte d'Azur and Southwest Research Institute reports possible new evidence of Planet 9. They have published their paper on the arXiv preprint server, and it has been accepted for publication in The Astrophysical Journal Letters .

In 2015, a pair of astronomers at Caltech found several objects bunched together beyond Neptune's orbit, near the edge of the solar system. The bunching, they theorized, was due to the pull of gravity from an unknown planet—one that later came to be called Planet 9.

Since that time, researchers have found more evidence of the planet, all of it circumstantial. In this new paper, the research team reports what they describe as additional evidence supporting the existence of the planet.

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Journal information: Astrophysical Journal Letters , arXiv

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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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Class 9 Science Case Study Questions Chapter 12 Sound

• Post author: studyrate
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Case study Questions in Class 9 Science Chapter 12 are very important to solve for your exam. Class 9 Science Chapter 12 Case Study Questions have been prepared for the latest exam pattern. You can check your knowledge by solving  Class 9 Science Case Study Questions  Chapter 12 Sound

Join our Telegram Channel, there you will get various e-books for CBSE 2024 Boards exams for Class 9th, 10th, 11th, and 12th.

In CBSE Class 9 Science Paper, Students will have to answer some questions based on Assertion and Reason. There will be a few questions based on case studies and passage-based as well. In that, a paragraph will be given, and then the MCQ questions based on it will be asked.

Sound Case Study Questions With Answers

Here, we have provided case-based/passage-based questions for Class 9 Science  Chapter 12 Sound

Case Study/Passage-Based Questions

Case Study 1: A violin and a flute may both be played at the same time in an orchestra. Both sounds travel through the same medium, that is, air and arrive at our ears at the same time. Both sounds travel at the same speed irrespective of the source. But the sounds receive are different. This is due to the different characteristics associated with the sound. Pitch is one of the characteristics. How the brain interprets the frequency of emitted sound is called its pitch. The faster the vibration of the source, the higher the frequency and the higher the pitch. The magnitude of the maximum disturbance in the medium on either side of the mean value is called the amplitude of the wave. It is usually represented by the letter (A).

The loudness or softness of a sound is determined basically by its amplitude. The amplitude of the sound wave depends upon the force with which an object is made to vibrate. If we strike a table lightly, we hear a soft sound because we produce a sound wave of less energy (amplitude).

The quality of timbre of a sound is that characteristic that enables us to distinguish one sound from another having the same pitch and loudness. The sound which is more pleasant is said to be of rich quality. A sound of a 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 the source of sound is higher

(b) Vibration of the source of sound is Lower

(c) Independent of vibration of the source of sound

(d) None of these

Answer: (a) Vibration of the source of sound is higher

(ii) Loudness and softness of sound depend upon

(a) Frequency of sound

(b) Amplitude of sound

(c) Wavelength of sound

Answer: (b) Amplitude of sound

(iii) Sound of single frequency is called

Answer: (b) Tone

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

Answer: 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) Determine which of the following has a higher pitch railway horn or guitar?

Answer: 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.

Case Study 2: Sound bounces off a solid or a liquid like a rubber ball bounces off a wall. Like the 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 that 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 hearing distinct echoes, the minimum distance of the obstacle from the source of sound must be 17.2 m. This distance will change with the temperature of the air. Another phenomenon of reflection of sound is reverberation. A sound created in a big hall will persist by repeated reflection from the walls until it is reduced to a value where it is no longer audible. The repeated reflection that results in this persistence of sound is called reverberation. Excessive reverberation is highly undesirable.

(i) Which of the following is true related to the 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 the same plane

(c) Both a and b are true.

Answer: (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

Answer: (c) 17.2m

(iii) Excessive reverberation is 

(a) Desirable phenomenon

(b) Undesirable phenomenon

(c) Does not exist

Answer: (b) Undesirable phenomenon

(iv) A person makes a sound near an 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?

Answer: 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.

Case Study 3:

Sound is a form of energy that produces a sensation of hearing. It is produced by the vibration of objects. When an object vibrates, it creates sound waves that travel through a medium, such as air, water, or solids. Sound waves are mechanical waves that require a medium for propagation. They travel in the form of compressions and rarefactions, creating a series of high-pressure and low-pressure regions. The characteristics of sound include pitch, loudness, and quality. Pitch is determined by the frequency of the sound waves, with higher frequencies corresponding to higher pitches. Loudness is related to the amplitude of the sound waves, with larger amplitudes resulting in louder sounds. The quality of sound refers to its timbre, which is influenced by the presence of overtones and harmonics. Understanding the properties and behavior of sound waves helps us comprehend various phenomena, such as the production of musical notes, the propagation of sound, and the phenomenon of echoes.

What is sound? a) A form of light energy b) A form of mechanical energy c) A form of electrical energy d) A form of heat energy Answer: b) A form of mechanical energy

How is sound produced? a) By the reflection of light waves b) By the absorption of heat energy c) By the vibration of objects d) By the flow of electrical current Answer: c) By the vibration of objects

What do sound waves require for propagation? a) Light b) Heat c) Medium d) Electricity Answer: c) Medium

What determines the pitch of a sound? a) The amplitude of the sound waves b) The frequency of the sound waves c) The loudness of the sound waves d) The quality of the sound waves Answer: b) The frequency of the sound waves

What is the quality of sound? a) The timbre of the sound b) The amplitude of the sound waves c) The loudness of the sound waves d) The pitch of the sound waves Answer: a) The timbre of the sound

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