FORCE AND LAWS OF MOTION

FORCE AND LAWS OF MOTION

VERY SHORT ANSWER TYPE QUESTIONS (VSAQ)

1. What are balanced forces? Ans :- Balanced forces are equal forces acting in opposite directions that cancel each o...

11. The fruits fall off the branches when a strong wind blows. Give reason. Ans :- Fruits stay at rest because of in...

21. What is inertia? Ans :- Inertia is the tendency of an object to resist changes to its motion. Heavier objects ha...

31. If a ball is thrown up in a moving train, it comes back to the person’s hands. Why? Ans :- This is because no ho...

41. What does the third law of motion state? Ans :- The third law states that for every action, there is an equal and...

SHORT ANSWER TYPE QUESTIONS (SAQ)

1. What are balanced forces, and what do they do? Ans :- Balanced forces are forces that are equal in magnitude but o...

2. How do unbalanced forces affect an object's motion? Ans :- Unbalanced forces occur when one force is stronger than...

3. What is momentum? Ans :- The momentum of an object is calculated by multiplying its mass by its velocity, and it...

4. Why are road accidents at high speeds very much worse than accidents at low speeds? Ans :- At high speeds, vehicl...

5. What is friction, and how does it affect motion? Ans :- Friction is a force that resists motion when two surfaces...

6. What happens when balanced forces are applied to an object? Ans :- When balanced forces act on an object, the obje...

7. What is Newton’s First Law of Motion? Ans :- Newton’s First Law, also known as the Law of Inertia, states that an...

8. What is Newton's First Law of Motion? Ans :- Newton's First Law states that an object remains at rest or in unifo...

9. How does inertia affect a person in a moving bus? Ans :- Inertia causes a person in a moving bus to continue movi...

10. Why do we give jerks to wet clothes before hanging them? Ans :- We give jerks to wet clothes to quickly remove w...

11. Explain our walking in terms of Newton’s third law of motion. Ans :- When we walk on the ground, our foot pushes...

12. What happens when a striker hits a pile of coins in carom? Ans :- When a striker hits the pile of coins, only th...

13. Can an object move forever without any force acting on it? Ans :- In theory, an object could keep moving forever...

14. Explain why some of the leaves may get detached from a tree if we vigorously shake its branch. Ans :- Some of th...

15. Why is it harder to push a heavy object compared to a lighter one? Ans :- Heavier objects have more mass, which...

16. How does inertia affect our daily experiences, such as when traveling in a car? Ans :- Inertia affects us when a...

17. How do action and reaction forces work when you push against the ground to walk? Ans :- When you push against th...

18. Why does a bullet move forward when a gun is fired, and what happens to the gun? Ans :- When a bullet is fired,...

19. State Newton’s second law of motion? Ans :- Newton’s Second law of motion states that when an unbalanced externa...

20. Define force and what are the various types of forces? Ans :- Force is defined as the push or pulls on an object...

21. State Newton’s first law of Motion? Ans :- Newton’s first law of motion is also called the law of Inertia. It st...

22. Explain inertia and momentum. Ans :- i. Inertia : Inertia is the natural ability of an object to resist changes...

23. Give example to show the effects of force. Ans :- (i) Put a ball on the ground and kick it with your foot. The...

24. When a force of 40 N is applied on a body it moves with an acceleration of 5 ms2. Calculate the mass of the body. A...

25. When a carpet is beaten with a stick, dust comes out of it. Explain. Ans :- When a carpet is beaten with a stick...

26. Why does the passenger sitting in a moving bus are pushed in the forward direction when the bus stops suddenly? Ans...

27. Why does the boat move backward when the sailor jumps in the forward direction? Ans :- The boat moves backward w...

LONG ANSWER TYPE QUESTIONS (LAQ)

1. What are balanced and unbalanced forces, and how do they affect the motion of an object? Ans :- Balanced forces a...

2. How does friction affect the motion of objects, and what role does it play in daily life? Ans :- Friction is a fo...

3. How does Newton's First Law of Motion, or the Law of Inertia, explain everyday experiences such as riding in a bus or...

4. Explain Newton's Third Law of Motion with examples of action and reaction forces in everyday situations. Ans :- N...

5. State all 3 Newton’s law of motion. Ans :- i. Newton’s I law of motion : Newton's First Law of Motion states tha...

6. Define force. What are different types forces? Ans :- Force : Force is a push or pull that causes an object to...

7. (a) What is friction? (b) What are the advantages of friction? or Why is friction necessary? Ans :- (a) The forc...

8. An object undergoes an acceleration of 8 ms–2 starting from rest. Find the distance travelled in 1 second. Ans :-...

9. State Newton’s third law of motion and how does it explain the walking of man on the ground? Ans :- Newton’s thir...

10. (i) What are the causes of friction? (ii) How can friction between any two surfaces can be reduced? or Describe s...

11. Why does a person while firing a bullet holds the gun tightly to his shoulders? Ans :- When a person fires a bul...

12. If action is always equal to the reaction, explain how a horse can pull a cart. Ans :- i. Here, we're looking a...

13. An automobile vehicle has a mass of 1500kg. What must be the force between the vehicle and road if the vehicle is to...

14. What is inertia? Explain different types of inertia. Ans :- Inertia : Inertia is the natural tendency of an obj...

15. Calculate the force required to impact to a car, a velocity of 30 ms–1 in 10 seconds. The mass of the car is 1,500 k...

16. What is the momentum of a body of mass 200g moving with a velocity of 15ms-1? Ans :- Given: Mass of body: m = 20...

17. Two objects, each of mass 1.5kg, are moving in the same straight line but in opposite directions. The velocity of ea...

18. Why do you fall in the forward direction when a moving bus breaks to a stop and fall back when it accelerates from r...

19. A force of 25N acts on a mass of 500g resting on a frictionless surface. What is the acceleration produced? Ans :-...

20. Why is it advised to tie any luggage kept on the roof of a bus with a rope? Ans :- i. It is advised to tie any...

21. A hockey ball of mass 200g traveling at 10ms-1 is struck by a hockey stick so as to return it along its original pat...

22. A stone of 1kg is thrown with a velocity of 20ms−1 across the frozen surface of a lake and comes to rest after trave...

23. Explain why is it difficult for a fireman to hold a hose, which ejects large amounts of water at a high velocity....

24. An object experiences a net zero external unbalanced force. Is it possible for the object to be traveling with a non...

NCERT SOLUTION

Page No. 91 1. Which of the following has more inertia? (a) A rubber ball and a stone of t...

4. Why do you fall in the forward direction when a moving bus apply brakes to stop and fall back when it accelerates...

Page No. 97 Exercises 1. An object experiences a net zero external unbalanced force. Is it...

5. A truck starts from rest and rolls down a hill with a constant acceleration. It travels a distance of 400 m in 20...

6. A stone of 1 kg is thrown with a velocity of 20 m s −1 across the frozen surface of a lake and comes to rest afte...

7. An 8000 kg engine pulls a train of 5 wagons, each of 2000 kg, along a horizontal track. If the engine exerts a fo...

8. An automobile vehicle has a mass of 1500 kg. What must be the force between the vehicle and road if the vehicle i...

Page No. 98 9. What is the momentum of an object of mass m, moving with a velocity v?(a) (mv...

10. Using a horizontal force of 200 N, we intend to move a wooden cabinet across a floor at a constant velocity. Wha...

11. According to the third law of motion when we push on an object, the object pushes back on us with an equal and o...

12. A hockey ball of mass 200 g travelling at 10 ms -1 is struck by a hockey stick so as to return it along its orig...

13. A bullet of mass 10g travelling horizontally with a velocity of 150 ms-1 strikes a stationary wooden block and c...

14. An object of mass 1 kg travelling in a straight line with a velocity of 10 ms -1 collides with and sticks to a s...

15. An object of mass 100 kg is accelerated uniformly from a velocity of 5 ms -1 to 8 ms -1 in 6s. Calculate the ini...

16. Akhtar, Kiran and Rahul were riding in a motorcar that was moving with a high velocity on an expressway when an...

17. How much momentum will a dumbbell of mass 10 kg transfer to the floor if it falls from a height of 80 cm ? Take...

2. Two persons manage to push a motorcar of mass 1200 kg at a uniform velocity along a level road. The same motorcar...

3. A hammer of mass 500 g, moving at 50 ms-1, strikes a nail. The nail stops the hammer in a very short time of 0.01...

4. A motorcar of mass 1200 kg is moving along a straight line with a uniform velocity of 90 km/h. Its velocity is sl...

SUMMARY

Introduction to Motion and Force In the last chapter, we discussed how objects move along a straight line by looking at...

Balanced and Unbalanced Forces Forces in physics can be classified as balanced or unbalanced depending on their effect...

First Law of Motion (Law of Inertia) Definition: The First Law of Motion states that an object will stay at rest or cont...

Inertia and Mass Inertia is the property of an object that describes its resistance to changes in its state of motion....

Second Law of Motion (Newton's Second Law) Newton's Second Law of Motion helps us understand how objects respond to for...

Numerical Problems Based on Momentum ❑ Example 1: What will be the momentum of a stone that has a mass of 10 kg whe...

Third Law of Motion Understanding the Third Law of Motion: The third law of motion states that whenever one object appli...