714 + Interview Questions in FORCE IN GENERAL AWARENESS Page 10 InterviewSolution

451.	Why do wrestlers rub powder on their hands before getting into the ring ?
Answer» In order to prevent their hands from slipping over their opponent’s body. The powder increases the friction.

Discussion

452.	State if the following statements are true or false.1. Friction wears down the parts of machi3. Friction helps us to grip the objects in our hand.4. Tyres of vehicles are provided with grooved designs to decrease friction.5. Friction is offered by all the three states of matter.
Answer» 1. True 2. False. Friction helps us with our walking or running. 3. True 4. False. Tyres of vehicles are provided with grooved designs to increase friction. 5. True

452.

State if the following statements are true or false.1. Friction wears down the parts of machi3. Friction helps us to grip the objects in our hand.4. Tyres of vehicles are provided with grooved designs to decrease friction.5. Friction is offered by all the three states of matter.

Answer»

1. True

2. False.

Friction helps us with our walking or running.

3. True

4. False.

Tyres of vehicles are provided with grooved designs to increase friction.

5. True

Discussion

453.	Take two balloons inflate them. Rub both with your hair. Bring them to closer to each other. Then they A) repels B) attracts C) no change D) we cannot say anything
Answer» Correct option is A) repels option A is correct *Repel*

Discussion

454.	How does the friction arise between the surfaces of two bodies in relative motion?
Answer» The force of friction is arised by the interlocking of the irregularities of the two surfaces.

Discussion

455.	The resistance to the movement of a body over the surface of another is A) force B) friction C) workdoneD) energy
Answer» Correct option is B) friction

Discussion

456.	A push or a pull is called A) friction B) pressure C) force D) none of these
Answer» Correct option is C) force

Discussion

457.	Name the two forces acting on a rocket immediately after leaving the launching pad.
Answer» The two forces acting on rocket are: 1. Force due to gravity vertically downward. 2. Frictional force of atmosphere.

457.

Name the two forces acting on a rocket immediately after leaving the launching pad.

Answer»

The two forces acting on rocket are:

1. Force due to gravity vertically downward.

2. Frictional force of atmosphere.

Discussion

458.	Some forces are acting without any contact of surfaces. Explain.
Answer» Some forces like magnetic force, electrostatic force and gravitational force act on other bodies without any contact of surfaces. This property is called the field force. As far as magnetic force concern, the magnets are surrounded by the magnetic lines of force which provide the magnets attractive and repelling forces. The same poles repel and the different poles attract. The electrostatic forces are exerted by a charged body on another charged or uncharged body. The charged body induces an opposite charge on the uncharged body and it gets attracted by the body. Here, the two bodies are at distance before the electrostatic forces are exerted. The earth attracts everybody even though they are at some distance. This force is called gravitational force or weight of the body. It varies at different places.

458.

Some forces are acting without any contact of surfaces. Explain.

Answer»

Some forces like magnetic force, electrostatic force and gravitational force act on other bodies without any contact of surfaces. This property is called the field force.

As far as magnetic force concern, the magnets are surrounded by the magnetic lines of force which provide the magnets attractive and repelling forces. The same poles repel and the different poles attract.

The electrostatic forces are exerted by a charged body on another charged or uncharged body. The charged body induces an opposite charge on the uncharged body and it gets attracted by the body. Here, the two bodies are at distance before the electrostatic forces are exerted.

The earth attracts everybody even though they are at some distance. This force is called gravitational force or weight of the body. It varies at different places.

Discussion

459.	No. of forces acting on acting on the block ‘B’ isA) 1 B) 2 C) 3D) 4
Answer» Correct option is B) 2

Discussion

460.	Name the forces acting on a plastic bucket containing water held above ground level in your hand. Why do the forces acting on the bucket do not bring a change in its state of motion?
Answer» The gravitational force acts as plastic bucket containing water held above ground level in your hand. Gravitational force does not bring change in state of bucket because equal amount of force is applied vertically upward.

Discussion

461.	Which one of these is not a contact force? A) Muscular force B) Frictional force C) Normal forceD) Magnetic force
Answer» D) Magnetic force option d ) *magnetic force*

Discussion

462.	Let the forces F1 and F2 act on the table in opposite directions, F1 > F2 , the Fnet = ……………. A) F1 – F2 B) F2 + F2 C) 0 D) 2F2 – F1
Answer» Correct option is A) F₁ – F₂ option A)*F1-F2*

Discussion

463.	Fig 1.35 shows two forces each of magnitude 10 N acting at the points A and B at a separation of 50 cm, in opposite directions. Calculate the resultant moment of the two forces about the point (i) A, (ii) B and (iii) O, situated exactly at the middle of the two forces.
Answer» (i) Perpendicular distance of point A from the force F = 10 N at B is 0.5m, while it is zero from the force F = 10 N at A Hence, moment of force about A is = 10 N × 0.5m = 5 Nm(clockwise) (ii) Perpendicular distance of point B from the force F = 10 N at A is 0.5m, while it is zero from the force F = 10 N at B Hence, moment of force about B is = 10 N × 0.5m = 5Nm (clockwise) (iii) Perpendicular distance of point O from either of the forces F = 10N is 0.25 m Moment of force F (=10N) at A about O = 10N × 0.25m = 2.5 Nm(clockwise) And moment of force F (=10N) at B about O = 10N × 0.25m=2.5 Nm(clockwise) Hence, total moment of the two forces about O = 2.5 + 2.5 = 5 Nm (clockwise)

463.

Fig 1.35 shows two forces each of magnitude 10 N acting at the points A and B at a separation of 50 cm, in opposite directions. Calculate the resultant moment of the two forces about the point (i) A, (ii) B and (iii) O, situated exactly at the middle of the two forces.

Answer»

(i) Perpendicular distance of point A from the force F = 10 N at B is 0.5m, while it is zero from the force F = 10 N at A

Hence, moment of force about A is

= 10 N × 0.5m = 5 Nm(clockwise)

(ii) Perpendicular distance of point B from the force F = 10 N at A is 0.5m, while it is zero from the force F = 10 N at B

Hence, moment of force about B is

= 10 N × 0.5m = 5Nm (clockwise)

(iii) Perpendicular distance of point O from either of the forces F = 10N is 0.25 m Moment of force F (=10N) at A about O = 10N × 0.25m

= 2.5 Nm(clockwise)

And moment of force F (=10N) at B about O

= 10N × 0.25m=2.5 Nm(clockwise)

Hence, total moment of the two forces about O

= 2.5 + 2.5 = 5 Nm (clockwise)

Discussion

464.	A body is thrown vertically upwards. Its velocity keeps on decreasing. What happens to its kinetic energy as its velocity becomes zero?
Answer» K.E. = 0 ∵ v = 0 ∵ K.E. = 1/2mv²

464.

A body is thrown vertically upwards. Its velocity keeps on decreasing. What happens to its kinetic energy as its velocity becomes zero?

Answer»

K.E. = 0

∵ v = 0

∵ K.E. = 1/2mv²

Discussion

465.	Short note on Sir Isaac Newton.
Answer» A British Physicist and Mathematician of high repute studied the color and composition of white light His studies on planetary motion led to his famous universal law of gravitation. He formulated three fundamental laws of mechanics called Newton‘s laws of motion. His main works are Principia and optics.

Discussion

466.	What is the characteristic of the cap of eye drop bottles?
Answer» The cap of an eye drop bottle is fitted with a dropper.

Discussion

467.	Why is the opening of a dropper very narrow?
Answer» The pressure produced by a given force is inversely proportional to the area of the surface on which the force acts. The opening of a dropper is very narrow. Hence, its area of cross-section is very small. As a result, even if the dropper has a small amount of ink it, its pressure can equal the atmospheric pressure. As the opening is narrow, it is easier to transfer the ink to the pen. The possibility of ink spilling is very low.

Discussion

468.	Mention the necessary conditions for a force to come into play.
Answer» Interaction between two objects is required for a force to come into play. The interaction of one object with other results in a force between two objects but no physical contact is necessary.

Discussion

469.	Play arm wrestling with your Mend. How can you explain the winning of the game by using the concept of net force?
Answer» The person we exerts more muscular force tends to win.

Discussion

470.	This force plays great role to do work play specially for human beings. A) Electrostatic force B) Muscular force C) Tension force D) Magnetic force
Answer» B) Muscular force

Discussion

471.	The air which is important to us is not escaping from the Earth. This is because of A) Normal forceB) Electrostatic force C) Gravitational force D) Above all
Answer» C) Gravitational force

Discussion

472.	What is a force? What changes can be produced by a force?
Answer» Force: A push or a pull of an object is called a force. Changes produced by a force: 1. A force can change the state of motion of an object. 2. A force can change the shape of an object.

472.

What is a force? What changes can be produced by a force?

Answer»

Force: A push or a pull of an object is called a force.

Changes produced by a force:

1. A force can change the state of motion of an object.

2. A force can change the shape of an object.

Discussion

473.	The wrongly mentioned part is A) a B) b C) c D) d
Answer» Correct option is B) b

Discussion

474.	State an example for a situation mentioned below in which a force: a) Changes the speed of an object. b) Changes the shape of an object. c) Changes the direction of an object.
Answer» a) Force changes the speed of an object: A ball at rest begins to move when a force is applied on it that shows force changes the speed of an object. b) Force changes the shape of an object: Take a plastic or metal scale placed between two bricks and put some weight at the centre of the scale. We observe that force changes its shape. c) Force changes the direction of an object: Kick a moving football with some angle then we can observe the change in the direction of football.

474.

State an example for a situation mentioned below in which a force: a) Changes the speed of an object. b) Changes the shape of an object. c) Changes the direction of an object.

Answer»

a) Force changes the speed of an object: A ball at rest begins to move when a force is applied on it that shows force changes the speed of an object.

b) Force changes the shape of an object: Take a plastic or metal scale placed between two bricks and put some weight at the centre of the scale. We observe that force changes its shape.

c) Force changes the direction of an object: Kick a moving football with some angle then we can observe the change in the direction of football.

Discussion

475.	The net force isForceMagnitudeDirectionF40 NTowards eastf20 NTowards westT30 NTowards upW30 NTowards downA) 20 N – Towards east B) 40 N – Towards west C) 20 N – Towards down D) None
Answer» A) 20 N – Towards east

Discussion

476.	Wrongly mentioned in the table isForceExertsa MagneticAround the magnetb ElectrostaticAround the chargec GravitationalAround the earthA) a B) b C) c D) None
Answer» Correct option is C) c

Discussion

477.	The force of a field is greater atA) a B) b C) c D) All are equal
Answer» Correct option is A) a

Discussion

478.	Study the above diagram. Why the given object does not move?A) Force – A > Force – B B) Force – B > Force – A C) both forces are equal. D) both forces are acting in opposite directions.
Answer» C) both forces are equal.

Discussion

479.	Study the figure given below. At which point, the pressure is greater?A) I B) II C) III D) IV
Answer» Correct option is C) III

Discussion

480.	The gravitational force acts between A) you and your friend B) you and earth C) you and moonD) above all
Answer» D) above all option d is correct *all of the above*

Discussion

481.	Siri wants to hit some pins in a balloon game as shown in the figure. To do so, where she should apply a force on the balloon?A) IB) II C) III D) IV
Answer» Correct option is B) II

Discussion

482.	Why is magnetic force considered as an action-at-a-distance force ?
Answer» Magnetic force comes into play even when the magnet and other object (like iron) are kept at a distance and not in direct contact with each other. Hence, magnetic-force is considered as an action- at-a-distance force.

Discussion

483.	The force acts between a charged balloon and piece of papers A) magnetic B) gravitational C) contact D) electrostatic
Answer» D) electrostatic option D ) electrostatic

Discussion

484.	Which are the following occation friction is beneficial and non beneficial1. striking a match stick on the side of a match box2. wear and tear of machines. 3. ability to hold objects 4. wearing out of tyres 5. walking 6. loss of fuel
Answer» Beneficial : 1, 3, 5 non beneficial : 2, 4, 6

484.

Which are the following occation friction is beneficial and non beneficial1. striking a match stick on the side of a match box2. wear and tear of machines. 3. ability to hold objects 4. wearing out of tyres 5. walking 6. loss of fuel

Answer»

Beneficial : 1, 3, 5

non beneficial : 2, 4, 6

Discussion

485.	Why does a charged balloon stick to a wall ?
Answer» It is due to the electrostatic force betwen the balloon and the wall. Opposite charges attract each other.

Discussion

486.	What do you understand by normal force ?
Answer» A force exerted by a surface to support the weight of a body in contact with it is called normal force. It is always perpendicular (right angles) to the surface. For example, when a book is kept on a table, the table exerts a normal force which acts upward on the book to support its weight.

Discussion

487.	Choose correct matching option:Group – AGroup – B1. Force responsible for attraction between two objects.a) Weight2. Force by which the Earth, the Moon and other massive large objects attracts another object.b) Mass3. Force applied by muscles of our body.c) Newton4. Force exerted by a surface as an object moves across it.d) Muscular5. The amount of substance contained in an object.e) Magnetic6. Units of force.f) Gravitational7. Force due to earth is calledg) FrictionalA) 1 – e, 2 – f, 3 – d, 4 – g, 5 – b, 6 – c, 7 – a B) 1 – a, 2 – b, 3 – c, 4 – d, 5 – e, 6 – f, 7 – g C) 1 – b, 2 – c, 3 – d, 4 – e, 5 – f, 6 – g, 7 – a D) 1 – c, 2 – d, 3 – e, 4 – f, 5 – g, 6 – a, 7 – b
Answer» A) 1 – e, 2 – f, 3 – d, 4 – g, 5 – b, 6 – c, 7 – a correct answer is 1st option

Discussion

488.	Pressure = ………… A) Force B) Force x area C) Area / force D) Force / area
Answer» D) Force / area

Discussion

489.	For the body at motion, the net force is A) ma B) oC) not equal to zero D) none of these
Answer» C) not equal to zero

Discussion

490.	For the body at rest, the net force is ………… A) ma B) not equal to zero C) 0 D) none of these
Answer» Correct option is C) 0

Discussion

491.	What is the relation between mass and inertia?
Answer» The property of an object because of which it resists to get disturbed its state is called Inertia. Inertia of an object is measured by its mass. Inertia is directly proportional to the mass. This means inertia increases with increase in mass and decreases with decrease in mass. A heavy object will have more inertia than lighter one. In other words, the natural tendency of an object that resists the change in state of motion or rest of the object is called inertia. Since a heavy object has more inertia, thus it is difficult to push or pul a heavy box over the ground than lighter one.

491.

What is the relation between mass and inertia?

Answer»

The property of an object because of which it resists to get disturbed its state is called Inertia. Inertia of an object is measured by its mass. Inertia is directly proportional to the mass. This means inertia increases with increase in mass and decreases with decrease in mass. A heavy object will have more inertia than lighter one.

In other words, the natural tendency of an object that resists the change in state of motion or rest of the object is called inertia.

Since a heavy object has more inertia, thus it is difficult to push or pul a heavy box over the ground than lighter one.

Discussion

492.	Which of the following has more inertia: (a) a rubber ball and a stone of the same size? (b) a bicycle and a train? (c) a five-rupees coin and a one-rupee coin?
Answer» Inertia is the measure of the mass of the body. The greater is the mass of the body; the greater is its inertia and vice-versa. (a) Mass of a stone is more than the mass of a rubber ball for the same size. Hence, inertia of the stone is greater than that of a rubber ball. (b) Mass of a train is more than the mass of a bicycle. Hence, inertia of the train is greater than that of the bicycle. (c) Mass of a five rupee coin is more than that of a one-rupee coin. Hence, inertia of the five rupee coin is greater than that of the one-rupee coin.

492.

Which of the following has more inertia: (a) a rubber ball and a stone of the same size? (b) a bicycle and a train? (c) a five-rupees coin and a one-rupee coin?

Answer»

Inertia is the measure of the mass of the body. The greater is the mass of the body; the greater is its inertia and vice-versa.

(a) Mass of a stone is more than the mass of a rubber ball for the same size. Hence, inertia of the stone is greater than that of a rubber ball.

(b) Mass of a train is more than the mass of a bicycle. Hence, inertia of the train is greater than that of the bicycle.

(c) Mass of a five rupee coin is more than that of a one-rupee coin. Hence, inertia of the five rupee coin is greater than that of the one-rupee coin.

Discussion

493.	Observing electrostatic forces : Take a balloon. Inflate it and tie up the open end. Now cut a paper into small pieces and place them on floor. Rub the balloon with a paper and using the balloon near the pieces of the paper. a) Are the bits of paper pulled towardsb) Why does the balloon pull or attracts the pieces of paper?c) Try to use pepper and salt in the place of pieces of paper. What do you observe?d) Why does the pen fall down?e) What is the force which pulls the pen down?f) If we keep the same pen on a table, it does not fall down. Why?
Answer» a) Yes, the bits of papers pulled towards balloon. b) When the balloon is rubbed with a paper it acquires charge and it induces opposite charge which brought near to it. So the pieces of paper are attracted by balloon. c) They do not attracted by the balloon. Gravitational force: It is our common experience that if a pen slips off from our hands it falls down to the floor. d) Some force is acting in downward direction. e) Gravitational force exerted by the earth. f) The gravitational force exerted by earth is balanced by normal force between pen and surface of the table.

493.

Observing electrostatic forces : Take a balloon. Inflate it and tie up the open end. Now cut a paper into small pieces and place them on floor. Rub the balloon with a paper and using the balloon near the pieces of the paper. a) Are the bits of paper pulled towardsb) Why does the balloon pull or attracts the pieces of paper?c) Try to use pepper and salt in the place of pieces of paper. What do you observe?d) Why does the pen fall down?e) What is the force which pulls the pen down?f) If we keep the same pen on a table, it does not fall down. Why?

Answer»

a) Yes, the bits of papers pulled towards balloon.

b) When the balloon is rubbed with a paper it acquires charge and it induces opposite charge which brought near to it. So the pieces of paper are attracted by balloon.

c) They do not attracted by the balloon. Gravitational force: It is our common experience that if a pen slips off from our hands it falls down to the floor.

d) Some force is acting in downward direction.

e) Gravitational force exerted by the earth.

f) The gravitational force exerted by earth is balanced by normal force between pen and surface of the table.

Discussion

494.	Visualizing magnetic field:Take a bar magnet and place it on a table. Place a thick white paper over it. On the paper, sprinkle fine powder of iron as shown in the figure. Tab the table or the paper gently with pen/pencil.a) Do you find the pattern of iron filings there?b) Rotate the magnet in different directions and do the same. How has the pattern changed?c) Why the iron filings set pattern around magnet?d) What is the space around the magnet called?
Answer» a) Yes b) In different directions that we will observe different patterns. c) Iron filings set themselves in a pattern because of magnetic field created by the magnet d) The space around magnet where its influence can be detected is called magnetic field.

494.

Visualizing magnetic field:Take a bar magnet and place it on a table. Place a thick white paper over it. On the paper, sprinkle fine powder of iron as shown in the figure. Tab the table or the paper gently with pen/pencil.a) Do you find the pattern of iron filings there?b) Rotate the magnet in different directions and do the same. How has the pattern changed?c) Why the iron filings set pattern around magnet?d) What is the space around the magnet called?

Answer»

a) Yes

b) In different directions that we will observe different patterns.

c) Iron filings set themselves in a pattern because of magnetic field created by the magnet

d) The space around magnet where its influence can be detected is called magnetic field.

Discussion

495.	Why we can walk easily on rough surfaces?
Answer» Between our steps and rough surfaces a sufficient friction force produces, so that we can walk easily on rough surface.

Discussion

496.	Observing electrostatic forces : Take a balloon. Inflate it and tie up the open end. Now cut a paper into small pieces and place them on floor. Rub the balloon with a paper and using the balloon near the pieces of the paper. a) Are the bits of paper pulled towards the balloon?a) Why does a stone thrown up into the sky fall back to the earth?b) Why do the rivers flow down to the sea?c) How does the earth hold the atmosphere?d) Is there any force pulling the objects towards earth?e) Where does gravitational force exists?
Answer» a) Due to gravitational pull. b) Due to gravitational force exerted by earth. c) Due to gravitational force exerted by earth. d) The force exerted by earth is gravitational force. e) The gravitational force exists everywhere in the universe between the objects having masses.

496.

Observing electrostatic forces : Take a balloon. Inflate it and tie up the open end. Now cut a paper into small pieces and place them on floor. Rub the balloon with a paper and using the balloon near the pieces of the paper. a) Are the bits of paper pulled towards the balloon?a) Why does a stone thrown up into the sky fall back to the earth?b) Why do the rivers flow down to the sea?c) How does the earth hold the atmosphere?d) Is there any force pulling the objects towards earth?e) Where does gravitational force exists?

Answer»

a) Due to gravitational pull.

b) Due to gravitational force exerted by earth.

c) Due to gravitational force exerted by earth.

d) The force exerted by earth is gravitational force.

e) The gravitational force exists everywhere in the universe between the objects having masses.

Discussion

497.	On what factor friction depends?
Answer» Friction force depends on the layers in contact.

Discussion

498.	Why it is not easy to walk on ice.
Answer» The friction force reduces to zero, so it is difficult to walk on ice.

Discussion

499.	a) Why does a stone thrown up into the sky fall back to the earth? b) Why do rivers flow down to the sea? c) How does the earth hold the atmosphere? d) Is there any force pulling the objects towards earth?
Answer» For all the above questions, the answer is ‘due to gravitational pull of the earth on the nearer bodies of the earth’.

Discussion

500.	Why do we fall down when we step on a banana peel?
Answer» The banana peel reduces the friction between ground and feet so we fall down when we step on a banana peel.

Discussion

Explore topic-wise InterviewSolutions in .

Why do wrestlers rub powder on their hands before getting into the ring ?

State if the following statements are true or false.1. Friction wears down the parts of machi3. Friction helps us to grip the objects in our hand.4. Tyres of vehicles are provided with grooved designs to decrease friction.5. Friction is offered by all the three states of matter.

Take two balloons inflate them. Rub both with your hair. Bring them to closer to each other. Then they A) repels B) attracts C) no change D) we cannot say anything

How does the friction arise between the surfaces of two bodies in relative motion?

The resistance to the movement of a body over the surface of another is A) force B) friction C) workdoneD) energy

A push or a pull is called A) friction B) pressure C) force D) none of these

Name the two forces acting on a rocket immediately after leaving the launching pad.

Some forces are acting without any contact of surfaces. Explain.

No. of forces acting on acting on the block ‘B’ isA) 1 B) 2 C) 3D) 4

Name the forces acting on a plastic bucket containing water held above ground level in your hand. Why do the forces acting on the bucket do not bring a change in its state of motion?

Which one of these is not a contact force? A) Muscular force B) Frictional force C) Normal forceD) Magnetic force

Let the forces F1 and F2 act on the table in opposite directions, F1 &gt; F2 , the Fnet = ……………. A) F1 – F2 B) F2 + F2 C) 0 D) 2F2 – F1

Fig 1.35 shows two forces each of magnitude 10 N acting at the points A and B at a separation of 50 cm, in opposite directions. Calculate the resultant moment of the two forces about the point (i) A, (ii) B and (iii) O, situated exactly at the middle of the two forces.

A body is thrown vertically upwards. Its velocity keeps on decreasing. What happens to its kinetic energy as its velocity becomes zero?

Short note on Sir Isaac Newton.

What is the characteristic of the cap of eye drop bottles?

Why is the opening of a dropper very narrow?

Mention the necessary conditions for a force to come into play.

Play arm wrestling with your Mend. How can you explain the winning of the game by using the concept of net force?

This force plays great role to do work play specially for human beings. A) Electrostatic force B) Muscular force C) Tension force D) Magnetic force

The air which is important to us is not escaping from the Earth. This is because of A) Normal forceB) Electrostatic force C) Gravitational force D) Above all

What is a force? What changes can be produced by a force?

The wrongly mentioned part is A) a B) b C) c D) d

State an example for a situation mentioned below in which a force: a) Changes the speed of an object. b) Changes the shape of an object. c) Changes the direction of an object.

The net force isForceMagnitudeDirectionF40 NTowards eastf20 NTowards westT30 NTowards upW30 NTowards downA) 20 N – Towards east B) 40 N – Towards west C) 20 N – Towards down D) None

Wrongly mentioned in the table isForceExertsa MagneticAround the magnetb ElectrostaticAround the chargec GravitationalAround the earthA) a B) b C) c D) None

The force of a field is greater atA) a B) b C) c D) All are equal

Study the above diagram. Why the given object does not move?A) Force – A &gt; Force – B B) Force – B &gt; Force – A C) both forces are equal. D) both forces are acting in opposite directions.

Study the figure given below. At which point, the pressure is greater?A) I B) II C) III D) IV

The gravitational force acts between A) you and your friend B) you and earth C) you and moonD) above all

Siri wants to hit some pins in a balloon game as shown in the figure. To do so, where she should apply a force on the balloon?A) IB) II C) III D) IV

Why is magnetic force considered as an action-at-a-distance force ?

The force acts between a charged balloon and piece of papers A) magnetic B) gravitational C) contact D) electrostatic

Which are the following occation friction is beneficial and non beneficial1. striking a match stick on the side of a match box2. wear and tear of machines. 3. ability to hold objects 4. wearing out of tyres 5. walking 6. loss of fuel

Why does a charged balloon stick to a wall ?

What do you understand by normal force ?

Pressure = ………… A) Force B) Force x area C) Area / force D) Force / area

For the body at motion, the net force is A) ma B) oC) not equal to zero D) none of these

For the body at rest, the net force is ………… A) ma B) not equal to zero C) 0 D) none of these

What is the relation between mass and inertia?

Which of the following has more inertia: (a) a rubber ball and a stone of the same size? (b) a bicycle and a train? (c) a five-rupees coin and a one-rupee coin?

Why we can walk easily on rough surfaces?

On what factor friction depends?

Why it is not easy to walk on ice.

a) Why does a stone thrown up into the sky fall back to the earth? b) Why do rivers flow down to the sea? c) How does the earth hold the atmosphere? d) Is there any force pulling the objects towards earth?

Why do we fall down when we step on a banana peel?

Let the forces F1 and F2 act on the table in opposite directions, F1 > F2 , the Fnet = ……………. A) F1 – F2 B) F2 + F2 C) 0 D) 2F2 – F1

Study the above diagram. Why the given object does not move?A) Force – A > Force – B B) Force – B > Force – A C) both forces are equal. D) both forces are acting in opposite directions.