NCERT Solutions Class 9 Science Chapter 11

NCERT Solutions for Class 9 Science Chapter 11: Work and Energy

Science is a fascinating subject and also equally tough to comprehend. Students find it challenging to understand the concepts. Also, Class 9 Science is one of the most important of their academics, as it prepares them for the  higher  classes. Understanding the concepts and theories is essential for students who wish to make a career in Science and other technical fields. 

Class 9 Science Chapter 11: Work and Energy helps create a solid foundation for CBSE Term II exam preparation. The chapter introduces new concepts to the students. First, it talks about the essential ideas of ‘work’ and ‘energy.’ Students will learn about the conception of work as well as the influence of constant force on it. It will be followed by the concept of energy- ; students will learn to comprehend different forms of energy, such as potential and kinetic energy. Furthermore, students will learn the concepts of the potential energy of an object at a height and the interconversion of energy.

Extramarks NCERT Solutions Class 9 Science Chapter 11 are available for the students. Our subject matter experts  prepare the solutions diligently  and follow the latest CBSE guidelines. Needless to say, they completely understand what’s legitimate  asper the board’s standards 

NCERT Solutions consist of objective, diagram-based, short, and long-type questions. It can be helpful for both CBSE term-wise exams and other competitive exams. The solution guide helps students lay a good foundation for their CBSE term II preparation. Further, it consists of a comprehensive methodology  and a detailed step-by-step procedure.All the key points in each section are being written in the format required in CBSE examinations. These solutions will help you save time and pay attention to other subjects as well. That itself reduces stress and anxiety to a great extent. Thus, it proves to be a great guide for students to step up for their preparation to get excellent results. 

Extramarks is one of India’s leading online learning platforms, trusted by many students.   Students of primary and secondary schools  can sign up at Extramarks  website and explore other study material as per their requirement. The solutions are prepared  to help the students in every way. They need not look for any other assistance elsewhere Extramarks has solutions to all your problems.  

Students can visit our website for the latest updates and exam-related news. Further, students can also refer to NCERT solutions Class 10, NCERT solutions Class 11, and NCERT solutions Class 12. 

Key Topics Covered In NCERT Solutions for Class 9 Science Chapter 11:

NCERT Solutions Class 9 Science Chapter 11 elaborates new terms and definitions related to work and energy. Work as well as energy are closely related terms that we use daily. Here, students learn more about force, power, energy, and how they are interlinked. For the best learning experience, students can go through all the topics and sub-topics mentioned in NCERT solutions for Class 9 Science Chapter 11. 

Some of the key topics featured in NCERT solutions for Class 9 Science Chapter 11 are: 

1. Work

In scientific terms work is said to be done when a force is applied on an object and the object is getting displaced in the direction of the force applied. 

So we can define work as: 

“Work is the product of the force applied on an object in the direction of the displacement and the magnitude of this displacement.”

Work is a dot product of two vectors, force, and displacement. Work is, therefore, a scalar quantity. Hence, Joule (J) is the SI unit for work.

W = F.d

  • W = Work done
  • F = Magnitude of the force applied
  • d = displacement caused due to force

Students can refer to NCERT Solutions Class 9 Science Chapter 11 to understand the fundamental concepts of work and energy. 

2. Energy

Energy is the ability to heat or do work. It is a scalar quantity, meaning it has  magnitude but not direction. It is conserved, which means that energy can be changed from one form to the another , but it can neither be   created nor destroyed. There are different  types of energy: kinetic and potential energy; light energy , sound energy, nuclear energy, and light energy.

Energy is derived from the Greek term energeia, or the French words in and ergon, which both mean work. The SI unit for energy is the joule (1 J), where 1J = 1kgm2s-2. Other units include the kilowatt-hour (kW-hr), British thermal unit (BTU), and calorie (c). 1 J = 1kgm2s-2. 

Further, students can solve NCERT Solutions Class 9 Science Chapter 11 with more examples of    potential energy and kinetic energy. 

3. Kinetic Energy

Kinetic energy can be defined as energy produced by an object because of its motion. Specific forces are required to accelerate an object. It takes work to apply force. The energy is then transferred to the object, making it move at constant velocity. The energy that is transferred to the object is called kinetic energy. It depends on its speed and mass.

Kinetic Energy Examples elaborated in NCERT Solutions Class 9 Science Chapter 11: 

  • Students must bear in their mind the formula for kinetic energy and look at some examples from everyday life.
  • Because of its higher velocity and large mass, an aeroplane can fly with vast kinetic energy.
  • After being thrown, a baseball will have high kinetic energy due to its high velocity and small size.
  • Because of its high velocity and mass, a downhill skier will have immense kinetic energy when coming down from the top.
  • A golf ball struck before it has kinetic energy is zero.
  • Asteroids that fall at incredible speeds have a lot of kinetic energy.
  • Because of its smaller mass, a car moving down the road uses less energy than a semi-truck.

4. Potential Energy

The potential energy is in the form of energy that is stored in an object because of some position relative to another position at rest. Here are three types of energy effects: chemical, nuclear, and potential electric. It can be calculated based on the object’s mass, distance, and height. It is measured in Joules.

Rate of Doing Work

Machines do not consume or transfer energy at the same rate. Agents that transfer energy do work at different rates. Machines are classified based on how quickly they can change the energy or work. Power is given to agents who complete a task within a specified time.

Power = work/time

Students can refer to NCERT Solutions Class 9 Science Chapter 11 to comprehend the rate of doing work and understand  power. In addition,  Class 9 science  Chapter 11 question answers with detailed explanations are available for the students. 

NCERT Solutions for Class 9 Science Chapter 11: Exercise & Solutions

Students can refer to the NCERT solutions for Class 9 Science Chapter 11, which is available on our Extramarks’ website. These resources can help the students cover the entire syllabus and provide an in-depth analysis of the topics. The solution is now made easier for the students with the comprehensive language. Each case and subtopic is elaborated well for the students to understand and even to supplement their studies to avoid the last-minute hassle. Our solution is the one-stop guide to preparing for the exams. 

Chapter 11: Work and Energy  This chapter plays a vital role as it introduces students to concepts related to force, energy, potential energy, and the law of energy conservation. The chapter also has plenty of numerical solutions and to solve examples and solutions students may require help. They can refer to these NCERT solutions to get in-depth knowledge on essential topics of work and energy and verify their answers and stay on the course. 

Students can refer below for specific exercises,examples, and solutions:

  • Class 9 Science Chapter 11: Exercise 11.2 – Example and Solutions
  • Class 9 Science Chapter 11: Exercise 11.3 – Example and Solutions
  • Class 9 Science Chapter 11: Exercise 11.4 – Example and Solutions
  • Class 9 Science Chapter 11: Exercise 11.5 – Example and Solutions
  • Class 9 Science Chapter 11: Exercise 11.6 – Example and Solutions
  • Class 9 Science Chapter 11: Exercise 11.7 – Example and Solutions
  • Class 9 Science Chapter 11: Exercise 11.8 – Example and Solutions
  • Class 9 Science Chapter 11: Exercise 11.9 – Example and Solutions

Along with this, students can also refer to other solutions for primary and secondary classes:

  • NCERT Solutions Class 1
  • NCERT Solutions Class 2
  • NCERT Solutions Class 3
  • NCERT Solutions Class 4
  • NCERT Solutions Class 5
  • NCERT Solutions Class 6
  • NCERT Solutions Class 7
  • NCERT Solutions Class 8
  • NCERT Solutions Class 9
  • NCERT Solutions Class 10
  • NCERT Solutions Class 11
  • NCERT Solutions Class 12

NCERT Exemplar for Class 9 Science:

Science is fascinating and requires an in-depth understanding of the concepts. Answering a range of questions can help you to understand these concepts better. This helps students to clear their concepts  and gives them  a better learning environment . In addition, solving different questions with a higher difficulty level will help students gain confidence in remembering the concepts. 

NCERT Exemplars help students to improve their understanding of issues.  There are numerous questions with varying  degrees of difficulty level.  In Chapter 11, there are  examples and solutions followed by chapter end exercises. . Students will get to practise  miscellaneous questions at the end of the exemplar. It’s better to go through the NCERT book first then try exemplar to maximise your potential.

The exemplar also has a few questions from NCERT Solutions Class 9 Science Chapter 11. Students will be able to examine different sub-topics, such as the law of conservation of energy, potential energy, kinetic energy and rate of doing work.

Key Features of NCERT Solutions for Class 9 Science Chapter 11:

Students are encouraged to study NCERT solutions and textbooks to prepare for the Class 9 Science annual exams. NCERT Solutions for Class 9 Science chapter 11 helps students to answer different types of questions and  to enhance their exam preparation so that they can face any kind of challenging question with ease and be confident.. These solutions use a simple language and a step-by, systematic approach to help students understand scientific concepts. Students can also refer to the chapter-wise NCERT Solutions to CBSE Class 9 Science to supplement their learning.

The key concepts from NCERT Solutions Class 9 Science Chapter 11 are listed here: 

  • It will help students revise concepts with examples provided, so they can easily understand them. 
  • The solution illustrates using scientific ideas in real life situations like designing a car, designing a power station, etc. to  clarify their concepts.
  • Our solution also provides essential information and background material relevant to the chapter. This will help students understand and remember significant points from the chapter easily. 
  • The notes are prepared by highly qualified and experienced faculty who meticulously follow the NCERT textbooks and CBSE guidelines to provide authentic and reliable study material.
  • The solutions are provided in an elementary language so as not to overwhelm students, but at the same time, they cover all the necessary details needed by students.
  • The explanations and examples of NCERT Solutions for Class 9 Science chapter 11 have been kept simple and easy to understand. The solution is arranged step-by-step, with each model and explanation marked by its questions.
  •  It’s important to go beyond the NCERT books by including solutions as an integral  part of your  study schedule. This encourages the students to master the topic and increases their confidence in achieving a high grade. Students swear by Extramarks because of the absolute trust and confidence it has built over the years. 

FAQs (Frequently Asked Questions)

NCERT solutions for class 9 Science Chapter 11 are designed to give students a clear idea of what they should be focusing on when preparing for exams. You will access multiple question banks and summaries of each topic and subtopic. All questions, answers, and explanations are clear, concise, understandable, and reliable to help you prepare for exams. The suitable study materials will allow you to gain the knowledge and understanding necessary for work and energy.

Kinetic energy is the amount of energy an object has due to its motion. It’s the work needed to propel a mass from its rest to its actual velocity. So kinetic energy is the energy required to move an object. Kinetic Energy can be seen in a person running or walking, throwing a baseball, and a crumb falling off a tabletop. Visit the Extramarks website or mobile app to learn more about the chapter.

Students can refer to our NCERT solutions for Class 9 Science chapter 11. It offers comprehensive and detailed answers to every type of question present. Students can practise with the solutions and understand the concepts with detailed  explanations. It also provides a plethora of  exercise questions which help students to prepare for their exams. It is available in  simple and easy  language. Above all, these solutions come handy especially during last minute preparation and saves time for further revision.