Courses
Courses for Kids
Free study material
Offline Centres
More
Store Icon
Store

NCERT Solutions for Class 8 Science Chapter 12 - Friction

ffImage
Last updated date: 27th Mar 2024
Total views: 505.5k
Views today: 8.05k
MVSAT 2024

NCERT Solutions for Class 8 Science Chapter 12 - Free PDF Download

Introduction

The study of Science is composed of fascinating and enthralling discoveries. The concept of Friction is best described in NCERT Solutions Class 8 Science Chapter 12 by Vedantu. Class 8 Science Chapter 12 NCERT Solutions is a great platform that provides the fundamentals of the chapter and accurate answers to complex numerical questions. NCERT Solutions Science Chapter 12 is what students require to ace their exams.  Students are free to explore and visualise the concept by using NCERT Solutions for Class 8th Science Chapter 12. 


Class:

NCERT Solutions For Class 8

Subject:

Class 8 Science

Chapter Name:

Chapter 12 - Friction

Content Type:

Text, Videos, Images and PDF Format

Academic Year:

2023-24

Medium:

English and Hindi

Available Materials:

Chapter Wise

Other Materials

  • Important Questions

  • Revision Notes


Subjects like Science, Maths, and English will become easy to study if you have access to NCERT Solution for Class 8 Science, Maths solutions and solutions of other subjects. You can also download NCERT Solutions for Class 8 Maths to help you to revise the complete syllabus and score more marks in your examinations.


Important Topics for Class 8 Science Chapter 12

The Topic Friction is given with all the subtopics that are included in the syllabus of NCERT Class 8 Science Chapter 12.

Section Name

Topic Name

12

Friction

12.1

Force of Friction

12.2

Factors affecting Friction

12.3

Friction: A Necessary Evil

12.4

Increasing and Reducing Friction

12.5

Wheels Reduce Friction

12.6

Fluid Friction


Important Points

Some very basic information related to friction are provided below.

  • The definition of friction states that friction is a type of force that opposes the relative motion between two surfaces in contact. Friction acts on both surfaces.

  • Factors that affect Friction are the nature of surfaces in contact and the state of smoothness or roughness of those surfaces. 

  • Friction is less for smooth surfaces and is independent of the area of contact.

  • Static friction is the force that is required to overcome friction the instant an object starts moving from rest.

  • Sliding friction is less than static friction.

  • Friction is responsible for walking, gripping, writing, transmitting energy and the wear and tear of various parts of machines.


Class 8 Science Chapter 12 Friction discusses the impacts and factors affecting friction. The chapter describes friction as the resistance that every item encounters when it moves across or through a surface or another medium. Without frictional force, an item would either not start moving or, if it was already moving, would not stop. All of these questions have been answered in the NCERT solutions PDF. The specialists who have a thorough understanding of the material have created the NCERT Solutions for Class 8 History and Social Science.


After finishing answering the questions in the textbook, students can consult these answers. It is highly recommended to consult the assigned textbook of the topic when studying for a test. All of the questions from the Class 8 Science Chapter 12 Friction NCERT textbook are included in the NCERT Solutions for Class 8 Science Chapter 12. Download the PDF to ace your preparations.


Some of the Major Topics Covered under Class 8 Science Chapter 12 - Friction

The following are some of the important topics that are covered in Chapter 12 of the Class 8 curriculum.

  • Friction

  • What Are the Causes of Friction?

  • Factors Affecting Friction

  • Types of Friction

  • Advantages of Friction

  • Disadvantages of Friction

Access NCERT Solutions for Science Class 8 Chapter 12 – Friction

1. Fill in the blanks
  • Friction opposes the ________ between the surfaces in contact with each other.

Ans: Motion

  • Friction depends on the _________ of surfaces.

Ans: Nature

  • Friction produces _________. 

Ans: Heat

  • Sprinkling of powder on the carrom board ________ friction.

Ans: Reduce

  • Sliding friction is ________ than the static friction.

Ans: Lesser


2. Four children were asked to arrange forces due to rolling, static and sliding frictions in a decreasing order. Their arrangements are given below. Choose the correct arrangement.
    1. rolling, static, sliding

  1. rolling, sliding, static

  2.  static, sliding, rolling

  3.  sliding, static, rolling

Ans: (c) Static, sliding, rolling.

Static Friction: When we move an object which is at rest. 

Sliding Friction: Acts on a body when it is moving. 

Rolling Friction: Here the area of contact is smallest when compared to static and sliding friction. 


3. Alida runs her toy car on dry marble floor, wet marble floor, newspaper and towel spread on the floor. The force of friction acting on the car on different surfaces in increasing order will be

a. Wet marble floor, dry marble floor, newspaper and towel.

b. Newspaper, towel, dry marble floor, wet marble floor.

c. Towel, newspaper, dry marble floor, wet marble floor

d. Wet marble floor, dry marble floor, towel, newspaper

Ans : (a) Wet marble floor, dry marble floor, newspaper and towel.

Friction will be more if the surface is rough and it will be less if the surface is smooth. Hence, wet marble floor, dry marble floor, newspaper and towel is the correct sequence of these surfaces when arranged according to the increase in the force of friction acting on the car.


4. Suppose your writing desk is tilted a little. A book kept on it starts sliding down. Show the direction of frictional force acting on it.

Ans: When a book slides down a table, frictional force always acts always opposite to the direction of motion and along the incline.

Force of friction will always be parallel to the surfaces in contact.


Friction Forcr


5. You spill a bucket of soapy water on a marble floor accidentally. Would it make it easier or more difficult for you to walk on the floor? Why?

Ans: It would be difficult to walk on the floor when soapy water falls on the floor then the friction reduces therefore the chances to slip increases, as a result it becomes difficult to walk. 

When there is no soapy water then there will be interlocking between the foot and the ground.

When soap water spills the interlocking gets spoilt as a result friction reduces.


6. Explain why sportsmen use shoes with spikes.

Ans: Spikes present on the shoes make the surface of the shoes rough. This increases the friction. As friction increases, the grip on the ground increases. This makes it easier for them to walk or run.


7. Iqbal has to push a lighter box and Seema has to push a similar heavier box on the same floor. Who will have to apply a larger force and why?

Ans:

  • Friction is directly proportional to mass. Heavier an object more force to be applied to move it.

  • Heavier box will press the floor surface harder as compared to the lighter box.

  • The two surfaces are pressed harder against each other, so the force required to overcome the interlocking is more in case of the heavier box.

  • So Seema has to apply more force as compared to Iqbal.


8. Explain why sliding friction is less than static friction.

Ans: During sliding, contact points do not get enough time to get interlocked properly. Friction forces come into play when irregularities present in the surface of the two objects in contact get interlocked with each other. When an object is in motion, the sliding friction is smaller than the static friction as the interlocking during motion is very small. Thus, sliding friction is less than static friction.


9. Give examples to show that friction is both a friend and a foe.

Ans:

Friction is a friend in the below ways:

  • It helps us to walk.

  • It helps us to hold things.

  • It helps in grinding.

  • It helps in construction purposes.

  • It makes matchstick ignition possible.

Friction as a foe in the below ways:

  • It opposes motion.

  • It produces a lot of heat which results in wastage of energy.

  • It brings about wear and tear of machinery parts.

  • It leads to the application of more power in machines.

  • It produces noise in the machines.


10. Explain why objects moving in fluids must have special shapes.

Ans: Special shapes experience less fluid friction therefore can move easily through fluids. When an object moves in fluid, fluid friction opposes the motion. So, to reduce the friction between object and fluids, the object is given a special shape known as streamlined shape.

An aeroplane is a good example for this. The air exerts some friction when the aeroplane moves through the air. This will be opposed by the motion of the aeroplane. In order to overcome this friction, the aeroplane has to apply a lot of force. This force is in turn a waste of energy. So, it is necessary to design the shape of the aeroplane in such a way that it experiences less fluid friction.


NCERT Solutions Class 8 Science Chapter 12 - Free PDF Download

Downloading NCERT Solutions for Class 8 Science Chapter 12 Friction PDF from the website and app is easy. The methodical approach to strengthening the foundation of the chapter guarantees the success of any student in their board exams. NCERT Solutions Class 8 Science Chapter 12 provides answers that help in mastering the concepts, and formulae and solving numerical problems curated by our subject experts. A student can breeze through their exam revision with ease. Chapter 12 Friction Class 8 NCERT Solutions are provided as a step-by-step guide for a student of any calibre.


NCERT Solutions for Class 8 Science Chapters

Chapter 12 - Friction

NCERT Class 8 Chapter 12 Friction is part of the Physics of CBSE Science textbook. It is the primary source for this topic. The term ‘friction’ is best described along with its factors and formulas in a simplified format. Additionally, the student is provided with diagrams and different schematics to understand its applications and purpose in our world. The terminology, illustrations and numerical problems are written in a simple step-by-step format to establish a strong foundation of the topic. Our subject experts have prepared these NCERT Solutions to provide an overall knowledge base for the chapter.


Class 8 Science Chapter-Wise Marks Weightage

Class 8th Science Chapter 12 has a weightage of 20 marks. This chapter is important from an exam point of view. Basic questions and complex numericals keep repeating in the Board exams from this subject. Hence, preparing from these study materials makes students score better. 


Here is more detail about the contents of Chapter 12 Friction Class 8:

12.1 Force of Friction (1 short )

12.2  Factors affecting Friction (2 MCQs, 1 short)

12.3. Friction: A Necessary Evil (1 long)

12.4  Increasing and Reducing Friction (1 short, 1 long)

12.5 Wheels reduce Friction (1 short)

12.6 Fluid Friction (2 MCQ’s, 1 short)


Why are NCERT Solutions for Class 8 Science Chapter 12 Important?

  • The solutions are provided topic-wise along with brief descriptions, simplified illustrations and detailed answers to numerical problems.

  • NCERT Solutions for Class 8 Science Chapter 12 Friction are prepared by a team of experts who make learning simple and fun.

  • Our simplified answers provide an easy understanding and a valuable learning experience for smooth exam revision.

  • NCERT Science (Physics) Class 8 Chapter 12 comes with important points and engaging activities to learn the concept practically.

  • Our syllabus helps you score better and aid you with complete revision.

  • Apart from that, these solutions contain all the solved questions/answers and exercises of the chapter.


Chapter wise NCERT Solutions for Class 8 Science


Along with this, students can also view additional study materials provided by Vedantu, for Class 8:


Benefits of Studying from Vedantu’s NCERT Solutions for Class 8 Science Chapter 12 Friction 

The following are some of the key benefits of practising the NCERT Solutions for Class 8 Science Chapter 12 Friction

  • NCERT solutions are curated by experts with a primary focus to cover all the important topics.

  • The solutions are in a simple, precise and easy-to-understand format.

  • The solutions are accurate and follow the CBSE pattern of answering questions.

  • The subject matter experts have provided well-explained solutions keeping the intellectual capacities of all students in mind so that it would help in better understanding the concepts for all.

  • Concepts are followed by examples for a better understanding of the theories.


Summary

Vedantu's NCERT Solutions for Class 8 Science Chapter 12 - "Friction" provide comprehensive insights into the fascinating world of friction. These solutions cover the fundamental concepts and principles related to frictional forces, making it easier for students to understand the role of friction in everyday life. With a focus on clarity and accuracy, Vedantu's commitment to education is evident, offering accessible and quality resources for students. These solutions not only enhance scientific comprehension but also empower students to appreciate the significance of friction in various applications, from transportation to industrial processes. Vedantu's dedication to promoting scientific literacy and excellence is commendable, making these solutions an essential part of students' science education.

FAQs on NCERT Solutions for Class 8 Science Chapter 12 - Friction

1. Explain the Concept of Sliding Friction and its Relation to the Mechanism of Static Friction.

Frictional forces play a key role when irregularities on the surface of an object are discovered even if the surface is smooth. This is observed when the irregularities of two surfaces come into contact with each other and get interlocked. Sliding friction or kinetic friction is a contact force that resists the sliding motion of two objects. Static friction is the force of friction observed on a stationary object. It is larger than sliding friction as the interlocking mechanism is very small.

2. What are Some Examples of Friction Observed in Our Daily Lives?

Friction is both a friend and a foe. Some instances where we see friction in action are as follows:

  • Walking or running up or down a hill.

  • The wear and tear of shoes after vigorous activity.

  • The contact between the pen and the paper and the motion of the pen while writing.

  • The damages are caused by continuous exposure to heat in heavy-duty machines as they are continuously run. Therefore, lubricants are used to decrease the wear and tear of these machines.

  • Rubbing our hands together to generate heat

3. What are the various types of friction? Explain.

There are four types of Friction:

  • Static Friction - The frictional force, which acts in between two surfaces, when both are at rest with respect to each other.

  • Sliding Friction - The frictional force acts between two surfaces that are sliding with respect to each other.

  • Rolling Friction - The resisting force acts between the motion of anybody that performs rolling motion.

  • Fluid Friction - When the frictional force acts between two layers of liquid flowing with respect to each other.

4. What is the cause of friction?

A surface is not completely smooth and always has some irregularities, which become the main cause of the force of friction that comes into play when two surfaces come in contact with each other. If we go into the details, the roughness of the surface and molecular adhesion of surface molecules are the main reason behind the friction of any surface. So, the surfaces which have more roughness tend to have more friction.

5. What is friction?

The force which is resistive in nature and comes into play due to the relative motion between two surfaces is known as friction. The direction of the force is always opposite to the direction of motion and it tends to oppose the motion of the body. It comes into play due to the irregularities in surfaces and molecular adhesion properties of the surfaces of the objects. It is mainly of 4 types.

6. List out the topics included in Chapter 12 of NCERT Solutions for Class 8 Science.

Following are the topics included in Chapter 12 of NCERT Solutions for Class 8 Science:

  • Force of Friction

It has one short answer

  • Factors affecting friction

It has two MCQs and one short answer

Friction: A Necessary Evil

It has one long answer

  • Increasing and Reducing Friction

It has one short and one long answer

  • Wheels Reduce Friction

It has one short answer

  • Fluid Friction

It has two MCQs and one short answer 

Students can download the PDF file of NCERT Solutions free of cost to study offline.

7. What is frictional force covered in Chapter 12 of NCERT Solutions for Class 8 Science?

The frictional force is the force that acts between two surfaces when there occurs any relative motion between them. It resists the motion between the surfaces. It is caused due to irregularities in the surface and the adhesion of molecules of one surface with another. The force of friction is also necessary for the motion and thus is also known as a necessary evil.  There are four types of frictional forces, static, sliding, rolling and fluid. To know more about Chapter 12 Class 8 Science, visit the Vedantu app and the website (vedantu.com).