NCERT Solutions for Class 8 Science Chapter 12 Friction

Edited By Vishal kumar | Updated on Apr 01, 2024 10:36 AM IST

NCERT Solutions Class 8 Science Chapter 12 – Access And Download Free PDF

NCERT solutions for class 8 science chapter 12 Friction: If you are a CBSE student in class 8, you may be one of those looking for solutions for NCERT class 8 chapter 12 friction. This is an important chapter for class 8 students. To score good marks, knowing the CBSE NCERT solutions for class 8 science chapter 12 friction would be an advantage. In this chapter, you will get to know the topics like forces of friction, factors affecting friction, why friction is necessary, what is increasing and decreasing friction, how wheels reduce friction, static friction, ball bearings, fluid friction, use of lubricants and more.

This Story also Contains

NCERT Solutions Class 8 Science Chapter 12 – Access And Download Free PDF
NCERT solutions for class 8 science chapter 12 friction: Solved Exercise Questions
NCERT Solutions For Class 8 Science- Chapter-Wise
NCERT Solutions For Class 8: Subject-Wise
Friction Class 8 NCERT Science Chapter: Topics
How to use chapter-wise NCERT solutions
Key Features of NCERT Solution for Class 8 Science

NCERT Solutions for Class 8 Science Chapter 12 Friction

You can also check the detailed NCERT solutions for class 8 science chapter 12 friction on this page. Other NCERT solutions for class 8 are also available to understand how to derive the answers to the various questions asked in each chapter and each exercise. This, in turn, will help in performing better in the exams and scoring very good marks. Now just that, a good understanding of the NCERT solutions for subjects science or maths will further aid in higher classes and entrance exams like JEE Main and NEET which are for engineering and medical courses respectively.

**As per the CBSE Syllabus for the academic year 2023-24, this chapter has undergone a renumbering and is now designated as Chapter 8.

NCERT solutions for class 8 science chapter 12 friction: Solved Exercise Questions

Q1. Fill in the blanks.

(a) Friction opposes the _____________ between the surfaces in contact with each other.
(b) Friction depends on the _____________ of surfaces.
(c) Friction produces __________.
(d) Sprinkling of powder on the carrom board ________ friction.
(e) Sliding friction is ___________ than the static friction.

Answer:

(a) Friction opposes the motion between the surfaces in contact with each other.
(b) Friction depends on the nature of surfaces.
(c) Friction produces heat.
(d) Sprinkling of powder on the carrom board reduces friction.
(e) Sliding friction is less than the static friction.

Q2. 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.

(a) rolling, static, sliding
(b) rolling, sliding, static
(c) static, sliding, rolling
(d) sliding, static, rolling

Answer:

Static friction > sliding friction > rolling friction.

Q3. 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

Answer:

The force of friction acting on the car on different surfaces in increasing order will be wet marble floor, dry marble floor, newspaper and towel. Therefore (a) is the correct answer.

Q4. 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.

Answer:

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The frictional force will be opposite to the direction of motion

Q5. 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?

Answer:

It would make it more difficult for us to walk on the marble floor since the frictional force would further decrease and thus our grip on the floor while walking would become even lesser.

Q6. Explain why sportsmen use shoes with spikes.

Answer:

Sportsmen use shoes with spikes to increase the grip between their feet and the ground by increasing the friction with the help of spikes. This aids them while running on the ground.

Q7. 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?

Answer:

Seema would have to apply a larger force as she would have to overcome a greater frictional force. The frictional force between two surfaces exists due to the interlocking of the irregularities on the surface. The magnitude of this frictional force depends on how tight this interlocking is which in this case depends on the weight of the boxes which is more in the case of Seema.

Q8. Explain why sliding friction is less than static friction.

Answer:

Sliding friction is less than static friction as the frictional force between two surfaces depends on the interlocking between the irregularities on the surfaces. This interlocking in case of sliding decreases as the contact points does not get enough time to interlock properly thus reducing the frictional force.

Q9. Give examples to show that friction is both a friend and a foe.

Answer:

Friction acting as a friend:

(a) It aids us to walk and cars to move on the roads.

(b)Fire can be ignited using friction.

Friction acting as a foe:

(a) It causes the efficiency of engines to decrease and also damages machinery.

(b) Friction causes the soles of shoes and tires to wear off.

Q10. Explain why objects moving in fluids must have special shapes.

Answer:

When an object is moving through a liquid there is an opposing force offered by the liquid against the motion of the object. To reduce this opposing force objects must have special shapes.

The subject matter experts at Careers360 have created a comprehensive class 8 science chapter 12 question answer that is designed to help students understand the concepts easily. The solutions are provided in a step-by-step format with diagrams, making it easier for students to follow along. The PDF version of the NCERT class 8 science chapter 12 solution can be downloaded by students for their convenience.

Additionally, the solutions for science class 8 chapter 12 cover a variety of question types, including fill-in-the-blanks, correct arrangement, and short answer type questions, giving students a well-rounded understanding of the chapter. Students can use these solutions to prepare for exams, revise the chapter, or simply deepen their understanding of the subject.

NCERT Solutions For Class 8 Science- Chapter-Wise

Chapter 1	NCERT solutions for class 8 science chapter 1 Crop Production and Management
Chapter 2	NCERT solutions for class 8 science chapter 2 Microorganisms Friend and Foe In Microorganisms
Chapter 3	NCERT solutions for class 8 science chapter 3 Synthetic Fibres and Plastics
Chapter 4	NCERT solutions for class 8 science chapter 4 Materials Metals and Non Metals
Chapter 5	NCERT solutions for class 8 science chapter 5 Coal and Petroleum
Chapter 6	NCERT solutions for class 8 science chapter 6 Combustion and Flame
Chapter 7	NCERT solutions for class 8 science chapter 7 Conservation of Plants and Animals
Chapter 8	NCERT solutions for class 8 science chapter 8 Cell Structure and Functions
Chapter 9	NCERT solutions for class 8 science chapter 9 Reproduction in Animals
Chapter 10	NCERT solutions for class 8 science chapter 10 Reaching the Age of Adolescence
Chapter 11	NCERT solutions for class 8 science chapter 11 Force and Pressure
Chapter 12	NCERT solutions for class 8 science chapter 12 Friction
Chapter 13	NCERT solutions for class 8 science chapter 13 Sound
Chapter 14	NCERT solutions for class 8 science chapter 14 chemical effects of Electric Current
Chapter 15	NCERT solutions for class 8 science chapter 15 Some Natural Phenomena
Chapter 16	NCERT solutions for class 8 science chapter 16 Light
Chapter 17	NCERT solutions for class 8 science chapter 17 Stars and the Solar System
Chapter 18	NCERT solutions for class 8 science chapter 18 pollution of air and water

NCERT Solutions For Class 8: Subject-Wise

Class 8 Science Chapter 12 NCERT Solutions: Important Formulas and Diagrams

Friction

Friction is a force that opposes the relative motion or attempts to oppose the motion between two objects in contact.
It always acts in the direction opposite to the direction of motion or attempted motion.

Types of Friction

Static Friction: This is the friction that opposes the initial motion of an object at rest. It's the maximum force of friction that can be applied before motion starts.
Kinetic Friction: Once an object is in motion, this friction opposes its motion.
Rolling Friction: Occurs when one object rolls over another. It's generally less than kinetic friction.

Coefficient of Friction (μ)

It's a measure of the frictional properties between two materials.
The formula for frictional force: Frictional force (F) = Coefficient of friction (μ) × Normal force (N)
Coefficient of friction = force of friction / normal force

Methods to Reduce Friction

Lubrication: Adding a lubricant (like oil or grease) between surfaces reduces friction.
Smoothing: Making surfaces smoother can reduce friction.
Ball bearings: These reduce friction in rotating parts.

Reducing Friction in Daily Life

Lubricating moving parts of machines.
Using ball bearings in machinery.
Polishing or smoothing surfaces.

Friction Class 8 NCERT Science Chapter: Topics

Force of friction
Factors affecting friction
Friction - a necessary evil
Increasing and reducing friction
Wheels reduce friction
Fluid friction
Ball Bearing
Drag
Fluid Friction
Friction
Interlocking
Lubricants
Rolling Friction
Sliding Friction
Static Friction

How to use chapter-wise NCERT solutions

Now that the NCERT solutions for class 8 science chapter 12 friction are done on this page, it's time to move to other chapters and topics as well. The list is given above. All you need to do is click on the given link and the NCERT chapter with solutions to all exercises will be displayed. Use them to understand and solve to score more marks in your exam.

Key Features of NCERT Solution for Class 8 Science

Comprehensive Coverage: The friction class 8 solutions provide comprehensive coverage of the topic, addressing various aspects of friction, its causes, effects, and practical applications.
Detailed Explanations: The friction class 8 NCERT Solutions offer detailed and easy-to-understand explanations for all the questions and concepts presented in the chapter. This helps students grasp the material effectively.
Real-Life Examples: The class 8 science chapter 12 NCERT solutions include real-life examples and scenarios to illustrate the concepts of friction, making it easier for students to relate to and understand the subject matter.
Variety of Question Types: The class 8 friction NCERT solutions cover various question types, including multiple-choice questions, short answer questions, long answer questions, and numerical problems. This diversity allows students to practice different problem-solving techniques.
Practical Applications: Many questions are designed to highlight the practical applications of friction in everyday life, helping students see the relevance of the topic beyond the classroom.
Step-by-Step Solutions: For friction class 8 questions and answers, step-by-step solutions are provided. These solutions guide students through the problem-solving process, enabling them to understand the methodology.
Conceptual Clarity: The science chapter 12 class 8 aims to enhance students' conceptual clarity by breaking down complex ideas into simple, understandable explanations.
Assessment and Practice: The questions and solutions serve as valuable tools for self-assessment and practice. Students can use them to test their understanding of the chapter and prepare for exams.
Exam Orientation: Many questions are designed with a focus on exam preparation, aligning with the CBSE curriculum and exam pattern.
Critical Thinking: Some questions encourage critical thinking, requiring students to analyze situations, make predictions, and draw conclusions based on their knowledge of friction.
Comprehensive Answers: The class 8 science ch 12 question answer provided for each question are comprehensive and well-explained, ensuring that students not only know the correct answer but also understand the underlying concepts.

Also Check NCERT Books and NCERT Syllabus here:

Frequently Asked Questions (FAQs)

1. Is friction an important topic for higher studies?

Yes, friction, force, motion and pressure are important topics that will be studied in Class 9 NCERT Science Syllabus and also in Class 11 NCERT Physics book

2. What is the role of friction?

Friction opposes the motion between the surfaces in contact with each other. If there is no frictional force we wont be able to walk.

3. What are the topic covered in friction class 8

The following topics are covered in the chapter friction:

Force of friction
Factors affecting friction
Friction - a necessary evil
Increasing and reducing friction
Wheels reduce friction
Fluid friction
Ball Bearing
Drag
Fluid Friction
Friction
Interlocking
Lubricants
Rolling Friction
Sliding Friction
Static Friction

4. What is μ in friction?

μ represents the coefficient of friction between two surfaces.

5. What is the value of μ?

The value of the coefficient of friction (μ) varies depending on the materials of the surfaces in contact and other factors such as temperature and pressure. It can range from 0 to 1 or even higher.

Also Read

NCERT Solutions for Class 8 Science Chapter 11 Force and Pressure

NCERT Solutions for Class 8 Science Chapter 10 Reaching The age of adolescence

NCERT Solutions for Class 8 Science Chapter 9 Reproduction in Animals

NCERT Solutions for Class 8 Science Chapter 7 Conservation of Plants and Animals

NCERT Solutions for Class 8 Science Chapter 3 Synthetic Fibres and Plastics

NCERT Solutions for Class 8 Science Chapter 2 Microorganisms Friend and Foe

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