What Is The Magnitude Of The Force Applied On The Block By The Finger In Animation 1

NCERT Exemplar Solutions Class 8 Scientific discipline Chapter 11 – Free PDF Download

NCERT Exemplar for Class 8 Science Chapter xi Force and Force per unit area add analytical thinking and trouble-solving ability on the topics provided in CBSE Grade 8 Chapter eleven. By Studying this Exemplar thoroughly, the skill of students and their comprehension is tested. This will assist them determine their strengths and weaknesses. NCERT Exemplar problems provided here are non meant to provide you merely with question banking concern for examinations simply are primarily meant to improve the quality of teaching/learning process in schools. Solving Exemplar will help you solve different kinds of questions and numerical which are very of import from the point of examinations.

Strength and pressure are one of the most important capacity of CBSE Class 8 Science. In this chapter, the students will larn near the bones concepts of force and pressure. To understand the concepts of force and pressure and to score good marks in the exam students must understand the basics of the chapter and solve the important questions. To assist students we have provided the NCERT Exemplar for Course 8 Science Chapter 11 Force and Pressure.

Download PDF of NCERT Exemplar Course 8 Scientific discipline Solutions for Chapter 11 – Force And Pressure

Access Answers to NCERT Exemplar Grade 8 Science Chapter xi – Forcefulness And Pressure

Multiple Choice Questions

1. In Fig 11.ane, two boys A and B are shown applying force on a block. If the block moves towards the right, which one of the following statements is correct?

(a) The magnitude of strength applied by A is greater than that of B.

(b) The magnitude of strength applied by A is smaller than that of B.

(c) The net force on the block is towards A.

(d) The magnitude of strength applied past A is equal to that of B.

Soln:

Answer is (a) Magnitude of force applied by A is greater than that of B.

Explanation:

The magnitude of force applied by A is bigger than that of B as a result of the block moves towards right i.due east. towards B.

2. In the circuit shown in Fig.11.2, when the excursion is completed, the hammer strikes the gong. Which of the following forcefulness is responsible for the motility of the hammer?

(a) gravitational force solitary

(b) electrostatic force alone

(c) magnetic strength alone

(d) frictional force alone

Soln:

Answer is (c) magnetic forcefulness alone

Explanation:

As electric electric current flows through the whorl it behaves like an electromagnet which creates magnetic force. Hence the answer is magnetic strength lonely.

3. During dry atmospheric condition, while combing pilus, sometimes we experience hair flight apart. The force responsible for this is

(a) force of gravity.

(b) electrostatic forcefulness.

(c) the force of friction.

(d) magnetic force.

Soln:

The answer is (b) electrostatic force.

Explanation:

On combing the hair, comb and hair get oppositely charged due to electrostatic force.

4. Fig.xi.3 shows a container filled with water. Which of the post-obit statements is correct nigh the pressure of h2o?

Soln:

(a) The pressure at A > Pressure at B > Pressure at C.

(b) The force per unit area at A = Pressure at B = Pressure at C.

(c) The force per unit area at A <  Pressure at B > Pressure level at C.

(d) The pressure at A <  Pressure at B.

Soln:

The respond is (d) Pressure at A < Force per unit area at B

Caption:

Increase in h2o leads to an increase in depth.

five. Two objects repel each other. This repulsion could be due to

(a) frictional forcefulness merely

(b) electrostatic forcefulness only

(c) magnetic force simply

(d) either a magnetic or an electrostatic force

Soln:

The answer is (d) either a magnetic or an electrostatic force

Caption:when two objects are experiencing repulsive force considering there may be an electrostatic strength or a magnetic force.

6. Which one of the post-obit forces is a contact force?

(a) force of gravity

(b) force of friction

(c) magnetic forcefulness

(d) electrostatic strength

Soln:

The respond is (b) force of friction

Caption:

Force of allure acts simply when the bodies are in contact.

seven. A water tank has four taps fixed at points A, B, C, D as shown in Fig. xi.4. The water will catamenia out at the same pressure from taps at

(a) B and C

(b) A and B

(c) C and D

(d) A and C

Soln:

Answer is (a) B and C

Explanation:

B and C are at the same level, hence pressure level will be the same at B and C.

8. A brick is kept in three different ways on a table as shown in Fig. xi.5. The pressure level exerted by the brick on the table will exist

(a) maximum in position A-C

(b) maximum in position B

(c) maximum in position

(d) equal in all cases.

Soln:

Answer is (a) maximum in position A-C

Explanation:

Since the area of contact is minimum pressure will be maximum in A.

Very Brusque Answer Questions

9. A ball of dough is rolled into a flat chapatti. Proper name the force exerted to change the shape of the dough.

Soln:

Muscular Strength.

10. Where do we apply a strength while walking?

Soln:

While walking we use force on the basis.

eleven. A daughter is pushing a box towards the east direction. In which direction should her friend push button the box so that information technology moves faster in the same direction?

Soln:

Towards the east.

12., In the circuit shown in Fig.11.six, when the key is closed, the compass needle placed in the matchbox deflects. Name the force which causes this deflection.

Soln:

Answer is Magnetic force.

13. During dry weather, clothes made of synthetic fibre oft stick to the pare. Which type of force is responsible for this phenomenon?

Soln:

Answer is Electrostatic force

14. While sieving grains, small pieces fall down. Which force pulls them downwards?

Soln:

Force of gravity.

15. Does the force of gravity human action on dust particles?

Soln:

Yes, the force of gravity act on dust particles.

16. A gas-filled airship moves up. Is the upwards force interim on information technology larger or smaller than the force of gravity?

Soln:

The upward force is larger than the forcefulness of gravity.

17. Does the strength of gravitation be between two astronauts in space?

Soln:

Yep, the force of gravitation exists betwixt two astronauts in space.

Brusk Answer Questions

18. A chapati maker is a car which converts balls of dough into chapati. What effect of force comes into play in this procedure?

Soln:

Force works on the dough to convert it to chapati.

19. Fig.eleven.7 shows a human being with a parachute. Name the strength which is responsible for his downward motion. Volition he come down with the aforementioned speed without the parachute?

Soln:

Strength of gravity is responsible for his downwards motion. If he comes down without parachute his speed will exist higher.

20. Two persons are applying forces on two reverse sides of a moving cart. The cart all the same moves with the same speed in the same management. What practise you infer about the magnitudes and direction of the forces practical?

Soln:

Force practical is of equal magnitude in the opposite direction hence the cart moves with the same speed in the same direction.

21. 2 thermocol assurance held close to each other move abroad from each other. When they are released, name the force which might be responsible for this phenomenon. Explicate.

Soln:

Two Thermocol balls held close to each other move away from each other, which is because of electrostatic force. The balls having similar charges move away due to repulsion betwixt similar charges.

22. Fruits detached from a tree autumn down due to strength of gravity. We know that a forcefulness arises due to the interaction between two objects. Name the objects interacting in this case.

Soln:

Earth and fruits.

23. A man is pushing a cart down a slope. All of a sudden the cart starts moving faster and he wants to slow it down. What should he practise?

Soln:

He should apply a force to pull the cart upwards the slope.

24. Fig. 11.eight shows a motorcar sticking to an electromagnet. Proper name the forces acting on the car? Which one of them is larger?

Soln:

Magnetic force (in the upward direction) force of gravity or the weight of the car (downward) act on car. Magnetic forcefulness is larger than the force of gravity.

Long Answer Questions

25. An archer shoots an arrow in the air horizontally. However, after moving some distance, the arrow falls to the ground. Proper name the initial force that sets the arrow in move. Explain why the arrow ultimately falls downwards.

Soln:

Archer puts muscular strength to stretch the string. This will modify the shape of the arrow. When the string is released arrow regains its original position which gives information technology the initial force to set the motion. Because of gravitational from it comes down towards after some time.

26. Information technology is hard to cut textile using a pair of pair of scissors with blunt blades. Explicate.

Soln:

The blunt blade has a larger area than shard edged blades. Considering of this, edgeless blade produces a low pressure which makes it difficult to cut the cloth. Whereas in sharp bract expanse is much is very less which increase the pressure produced. This makes the cutting of material easier with sharp blades.

27. 2 rods of the same weight and equal length have different thickness. They are held vertically on the surface of sand as shown in Fig.11.ix. Which ane of them will sink move? Why?

Soln:

In Rod B area of contact is smaller. Hence the weight of the rod (Strength) produces more pressure. In Case of the rod, the aforementioned force produces less pressure.

28. Two women are of the same weight. I wears sandals with pointed heels while the other wears sandals with flat soles. Which 1 would feel more comfy while walking on a sandy beach? Give reasons for your answer.

Soln:

Women's height are same and they use the aforementioned weight when they walk. But women wearing sandal with a apartment heel will be more comfy while walking on a sandy beach. This is because apartment soles

have larger area compared to the sandals with pointed heels. Also, the pressure level exerted by the

pointed heels will be more compared to that with sandals having apartment soles. This pressure level will make the sandals with pointed soled sink in the sand which will make difficult to walk on sand.

29. It is much easier to burst an inflated airship with a needle than past a finger. Explain.

Soln:

The pressure exerted on an inflated airship by the needle will be more as it has a smaller expanse of contact compared to the finger. This larger pressure pierces the surface of the balloon easily which will brand the airship burst.

xxx. Detect the vessels A, B, C and D shown in Fig.11.x carefully.

The volume of water taken in each vessel is equally shown. Conform them in the order of decreasing pressure level at the base of each vessel. Explain.

Soln:

B, D, A, C. Considering the pressure level of a liquid column depends upon the peak of the liquid cavalcade and not on volume of the liquid.

Subtopics of CBSE syllabus Class 8 Science Chapter 11 Force and Pressure

1. Force – A Push or Pull
2. Forces are due to an Interaction
3. Exploring Forces
4. A Force can Change the State of Motion
5. Strength tin can Change the Shape of an Object
6. Contact Forces
7. Non-Contact Forces
8. Pressure level
9. Pressure Exerted by Liquids and Gases
10. Atmospheric Pressure.

BYJU'S presents outstanding NCERT Solutions, report materials, Sample papers, previous year question papers, Videos and animation for a thorough understanding and to memorise the topic for a longer menstruum. To get access to all the study materials nosotros provide, logon to BYJU'Due south website or download BYJU'S Learning App.

Oftentimes Asked Questions on NCERT Exemplar Solutions for Class 8 Scientific discipline Chapter xi

What are the topics covered under Affiliate 11 of NCERT Exemplar Solutions for Class 8 Scientific discipline?

The topics covered under the Chapter 11 of NCERT Exemplar Solutions for Class 8 Science are –
one. Force – A Push or Pull
2. Forces are due to an Interaction
three. Exploring Forces
4. A Force can Change the State of Motion
5. Force can Change the Shape of an Object
vi. Contact Forces
seven. Non-Contact Forces
8. Pressure level
9. Pressure Exerted by Liquids and Gases
ten. Atmospheric Pressure.

What are non-contact forces in Chapter 11 of NCERT Exemplar Solutions for Class viii Scientific discipline?

Forces that human activity through spaces without making straight contact with the body are called not-contact forces. Examples of non-contact forces are: gravitational force, electrostatic force and magnetic force. The force exerted past a magnet on other magnets is chosen magnetic force. Magnetic strength and electrostatic force human activity on an object from a distance, that's the reason they are not-contact forces. The forcefulness of gravity is an attractive force that is exerted by the Earth on objects, which makes them fall to the land. The weight of a body is the force that is pulled by the globe towards the center. This concept can exist conspicuously understood by the students using the NCERT Exemplar Solutions created by the faculty at BYJU'S. The solutions comprise explanations provided in a comprehensive manner to boost the examination preparation of students.

Can students rely on the NCERT Exemplar Solutions for Course viii Science Affiliate 11 from BYJU'S?

BYJU'S NCERT Exemplar Solutions for Class eight Science Chapter 11 are created to assistance students in focusing on key ideas. Every element is meticulously described to improve students' conceptual agreement. The solutions also include a diverseness of shortcut approaches for finer remembering the principles. While answering textbook questions, students tin refer to the solutions and comprehend the fashion of answering them without difficulty.

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