Force and Laws of Motion

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Learning Objectives

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Learning Objectives

Understand the concept of force and its effects on motion.
Explain the relationship between force, mass, and acceleration (Newton's Second Law).
Describe the principle of inertia and its implications in everyday scenarios.
Analyze the effects of unbalanced forces on the motion of objects.
Illustrate the action-reaction forces as per Newton's Third Law.
Apply the laws of motion to practical examples and experiments.

Revision Notes & Summary

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Chapter 8: Force and Laws of Motion

Introduction

Motion of an object can be uniform or non-uniform.
Force is required to change the state of motion of an object.

Concept of Force

Force can be described as a push, hit, or pull.
Effects of force include:
- Changing the magnitude of velocity (speeding up or slowing down).
- Changing the direction of motion.
- Changing the shape and size of objects.

Newton's Laws of Motion

First Law of Motion

An object remains at rest or in uniform motion unless acted upon by an unbalanced force.
Inertia: The natural tendency of objects to resist changes in their state of motion.
- Example: A person falls backward when a bus suddenly starts moving.

Second Law of Motion

The rate of change of momentum is proportional to the applied unbalanced force.
Formula: F = ma (Force = mass × acceleration)

Third Law of Motion

For every action, there is an equal and opposite reaction.
Example: When a sailor jumps forward from a boat, the boat moves backward.

Activities to Illustrate Concepts

Activity 8.1: Using carom coins to demonstrate inertia.
Activity 8.4: Children on carts throwing a sandbag to observe different accelerations.

Important Diagrams

Diagram 8.1

Description: Pushing, pulling, or hitting objects changes their state of motion.

Diagram 8.2

Description: Illustrates a person jumping from a boat to a dock, demonstrating action and reaction forces.

Diagram 8.6

Description: Shows a carom coin being hit and the inertia of the remaining coins.

Diagram 8.9

Description: Velocity-time graph of a ball showing uniform deceleration.

Summary of Key Points

Force is essential for changing motion.
Newton's laws explain the relationship between force and motion.
Inertia is a key concept in understanding motion.

Exam Tips & Common Mistakes

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Common Mistakes and Exam Tips

Common Pitfalls

Misunderstanding Inertia: Students often confuse inertia with mass. Remember, inertia is the tendency of an object to resist changes in its state of motion, while mass is a measure of that inertia.
Forgetting the Direction of Forces: When analyzing problems involving forces, students may neglect to consider the direction of the forces acting on an object, which can lead to incorrect conclusions about motion.
Confusing Newton's Laws: It is common to mix up the first and second laws of motion. Ensure you understand that the first law deals with inertia and the second law relates to the relationship between force, mass, and acceleration.

Exam Tips

Draw Diagrams: When faced with problems involving forces and motion, sketching diagrams can help visualize the situation and clarify the forces at play.
Use Units Consistently: Always check that you are using the correct units for mass (kg), force (N), and acceleration (m/s²) to avoid calculation errors.
Practice with Real-Life Examples: Relate concepts to everyday experiences, such as how seatbelts work (inertia) or how pushing a stationary object requires force, to reinforce understanding.
Review Key Formulas: Familiarize yourself with important equations, such as F = ma (force equals mass times acceleration) and the concept of momentum, to ensure you can apply them correctly in exam scenarios.

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Practice Test – MCQs, True/False

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Multiple Choice Questions

3 kg m/s

1.5 kg m/s

2 kg m/s

0.5 kg m/s

Correct Answer: A

Solution:

The change in momentum is given by the formula:

\Delta p = m(v_f - v_i)

, where

m = 0.2 \text{ kg}

v_f = -5 \text{ m/s}

, and

v_i = 10 \text{ m/s}

. Thus,

\Delta p = 0.2(-5 - 10) = 0.2(-15) = -3 \text{ kg m/s}

. The magnitude is 3 kg m/s.

3 kg m/s

1.5 kg m/s

2 kg m/s

0.5 kg m/s

Correct Answer: A

Solution:

Change in momentum is given by

\Delta p = m(v_f - v_i)

. Here,

m = 0.2 \text{ kg}

v_f = -5 \text{ m/s}

, and

v_i = 10 \text{ m/s}

. Thus,

\Delta p = 0.2(-5 - 10) = -3 \text{ kg m/s}

. The magnitude is 3 kg m/s.

Due to the force of gravity.

Due to the inertia of the leaves.

Due to the wind resistance.

Due to the friction between leaves and air.

Correct Answer: B

Solution:

The leaves tend to remain in their state of rest due to inertia, and when the branch is shaken, they detach.

3 J

6 J

15 J

30 J

Correct Answer: B

Solution:

The potential energy stored in a compressed spring is given by

PE = \frac{1}{2} k x^2

, where

k

is the spring constant and

x

is the compression. Substituting the given values,

PE = \frac{1}{2} \times 150 \times (0.2)^2 = 6 \text{ J}

1200 N

2400 N

3000 N

6000 N

Correct Answer: B

Solution:

The average force exerted can be calculated using the formula

F = \frac{\Delta p}{\Delta t}

, where

\Delta p

is the change in momentum and

\Delta t

is the time. The initial momentum

p_i = mv = 0.02 \times 300 = 6 \text{ kg m/s}

, and the final momentum

p_f = 0

. Thus,

\Delta p = 6 - 0 = 6 \text{ kg m/s}

. Therefore,

F = \frac{6}{0.05} = 120 \text{ N}

5 m/s

15 m/s

10 m/s

20 m/s

Correct Answer: B

Solution:

The change in velocity is the final velocity minus the initial velocity. Since the ball changes direction, the change is 5 m/s - (-10 m/s) = 15 m/s.

2 m/s²

5 m/s²

10 m/s²

20 m/s²

Correct Answer: B

Solution:

Using Newton's second law,

F = ma

, where

F = 10 \text{ N}

and

m = 2 \text{ kg}

. Thus,

a = \frac{F}{m} = \frac{10}{2} = 5 \text{ m/s}^2

0.2 m

0.1 m

0.4 m

0.3 m

Correct Answer: B

Solution:

The compression distance of the spring can be calculated using Hooke's Law,

F = kx

, where

F

is the force applied,

k

is the spring constant, and

x

is the compression distance. Rearranging for

x

, we have

x = \frac{F}{k} = \frac{50}{250} = 0.2 \text{ m}

6 N to the right

14 N to the right

6 N to the left

4 N to the right

Correct Answer: A

Solution:

The net force is calculated by subtracting the frictional force from the applied force:

F_{net} = 10 \text{ N} - 4 \text{ N} = 6 \text{ N}

. Since the applied force is greater, the net force is 6 N to the right.

0.75 m/s

1.5 m/s

0.5 m/s

1 m/s

Correct Answer: A

Solution:

Using the conservation of momentum, the initial momentum is zero. After firing, the momentum of the bullet and gun must be equal and opposite. Thus,

m_b v_b = m_g v_g

, where

m_b = 0.01 \text{ kg}

v_b = 150 \text{ m/s}

m_g = 2 \text{ kg}

. Solving for

v_g

, we have

v_g = \frac{m_b v_b}{m_g} = \frac{0.01 \times 150}{2} = 0.75 \text{ m/s}

Forward

Backward

Upward

Downward

Correct Answer: B

Solution:

The recoil force on the gun is in the opposite direction to the force propelling the bullet, which is backward.

The boat moves towards the dock.

The boat remains stationary.

The boat moves away from the dock.

The boat sinks.

Correct Answer: C

Solution:

According to Newton's Third Law of Motion, the action of jumping forward causes a reaction that moves the boat backward.

1000 J

2000 J

5000 J

10000 J

Correct Answer: C

Solution:

The work done on the object is equal to the change in kinetic energy, given by

W = \Delta KE = \frac{1}{2} m v^2 - \frac{1}{2} m u^2

, where

u = 0

(initial velocity). Thus,

W = \frac{1}{2} \times 100 \times 10^2 = 5000 \text{ J}

Law of conservation of energy

Law of inertia

Newton's Third Law of Motion

Law of conservation of momentum

Correct Answer: B

Solution:

The principle demonstrated is the law of inertia, where the coin tends to remain in its state of rest and falls directly into the cup when the card is flicked away.

0 N

100 N

200 N

400 N

Correct Answer: C

Solution:

Since the cabinet is moving at a constant velocity, the net force is zero. Therefore, the friction force must equal the applied force, which is 200 N.

A balanced force

An unbalanced force

No force

A gravitational force

Correct Answer: B

Solution:

Newton's First Law of Motion states that an object will remain at rest or in uniform motion unless acted upon by an unbalanced force.

The boat moves towards the dock.

The boat remains stationary.

The boat moves away from the dock.

The boat sinks.

Correct Answer: C

Solution:

According to Newton's Third Law, for every action, there is an equal and opposite reaction. When the person jumps towards the dock, the boat moves in the opposite direction, away from the dock.

1 m/s

2 m/s

3 m/s

4 m/s

Correct Answer: A

Solution:

Using conservation of momentum:

m_1v_1 = m_2v_2

, where

m_1 = 0.01 \text{ kg}

v_1 = 200 \text{ m/s}

m_2 = 2 \text{ kg}

. Solving for

v_2

gives

v_2 = \frac{0.01 \times 200}{2} = 1 \text{ m/s}

Because it is moving faster.

Because it has more mass.

Because it is longer.

Because it is on tracks.

Correct Answer: B

Solution:

Inertia is directly related to mass. A train has more mass than a small cart, thus it has more inertia.

1 m/s

1.5 m/s

0.5 m/s

2 m/s

Correct Answer: C

Solution:

According to the conservation of momentum, the total momentum before and after the jump must be equal. Let the velocity of the boat be

v_b

. Initial momentum is 0 because both are at rest. Final momentum is

60 \times 3 + 120 \times (-v_b) = 0

. Solving for

v_b

, we get

v_b = 0.5

m/s.

Both carts will move towards each other.

Both carts will move away from each other.

The carts will remain stationary.

Only one cart will move.

Correct Answer: B

Solution:

When the bag is thrown, the action of throwing causes a reaction that moves the carts away from each other due to conservation of momentum.

1.5 kg m/s

3 kg m/s

0.5 kg m/s

2 kg m/s

Correct Answer: A

Solution:

Initial momentum =

0.2 \times 10 = 2

kg m/s. Final momentum =

0.2 \times (-5) = -1

kg m/s. Change in momentum =

|2 - (-1)| = 3

kg m/s.

A rubber ball and a stone of the same size

A bicycle and a train

A five-rupees coin and a one-rupee coin

A feather and a metal ball of the same size

Correct Answer: B

Solution:

Inertia is the resistance of an object to change its state of motion, and it is directly related to the mass of the object. A train has more mass than a bicycle, thus it has more inertia.

Due to gravity

Due to inertia

Due to friction

Due to air resistance

Correct Answer: B

Solution:

According to the law of inertia, an object in motion tends to stay in motion with the same speed and in the same direction unless acted upon by an unbalanced force. When the bus stops, your body tends to continue moving forward.

A car accelerating from rest.

A ball rolling on a frictionless surface maintaining its velocity.

A rocket launching into space.

A spring being compressed by a force.

Correct Answer: B

Solution:

Newton's First Law of Motion states that an object will remain at rest or in uniform motion in a straight line unless acted upon by an external force. A ball rolling on a frictionless surface maintaining its velocity perfectly illustrates this law, as it continues its motion without any external forces acting on it.

4.9 m/s²

9.8 m/s²

5.0 m/s²

8.5 m/s²

Correct Answer: A

Solution:

The acceleration

a

is given by

a = g \sin \theta

, where

g = 9.8 \text{ m/s}^2

and

\theta = 30^\circ

. Thus,

a = 9.8 \times \sin 30^\circ = 4.9 \text{ m/s}^2

The coin moves with the card.

The coin falls straight down.

The coin remains in place.

The coin flies upwards.

Correct Answer: B

Solution:

Due to inertia, the coin tends to remain in its state of rest and falls straight down into the cup when the card is flicked away.

The block will accelerate towards Y.

The block will move with constant velocity towards Y.

The block will not move.

The block will move towards X.

Correct Answer: B

Solution:

If the applied force is equal to the frictional force, the net force on the block is zero. According to Newton's First Law, the block will move with a constant velocity towards Y.

6000 N

3000 N

1500 N

7500 N

Correct Answer: A

Solution:

The change in velocity

\Delta v = 0 - 20 = -20 \text{ m/s}

. Using the formula for force,

F = m \cdot a

, where

a = \frac{\Delta v}{\Delta t} = \frac{-20}{5} = -4 \text{ m/s}^2

. Thus,

F = 1500 \times (-4) = -6000 \text{ N}

. The magnitude is 6000 N.

0.75 m/s

0.5 m/s

0.25 m/s

1 m/s

Correct Answer: C

Solution:

Using conservation of momentum, the total initial momentum is zero. Let

v

be the velocity of the first cart. The equation is:

30v + 30 \times 0.5 = 0

. Solving for

v

, we get

v = -0.5 \times 0.5 = -0.25 \text{ m/s}

. The magnitude is 0.25 m/s.

The boat moves towards the dock.

The boat remains stationary.

The boat moves away from the dock.

The boat sinks.

Correct Answer: C

Solution:

According to Newton's Third Law of Motion, for every action, there is an equal and opposite reaction. As the person jumps towards the dock, the boat experiences an equal and opposite force, causing it to move away from the dock.

It stops at the bottom of the incline.

It rolls up to the same height from which it was released.

It rolls indefinitely without stopping.

It rolls back to its starting point.

Correct Answer: B

Solution:

According to Galileo's observations, a marble will roll up to the same height it was released from if the inclines are equal.

50 N

30 N

20 N

40 N

Correct Answer: A

Solution:

The acceleration

a

can be calculated using the formula

a = \frac{v_f - v_i}{t} = \frac{8 - 5}{6} = 0.5 \text{ m/s}^2

. The force

F

is then given by

F = ma = 100 \times 0.5 = 50 \text{ N}

2400 N

4800 N

6000 N

7200 N

Correct Answer: B

Solution:

Initial momentum

p_i = 1200 \times 20 = 24000 \text{ kg m/s}

. Final momentum

p_f = 0

. Change in momentum

\Delta p = -24000 \text{ kg m/s}

. Force

F = \frac{\Delta p}{\Delta t} = \frac{-24000}{5} = -4800 \text{ N}

. Magnitude is 4800 N.

Both carts will move towards each other.

Both carts will move away from each other.

The carts will remain stationary.

Only the cart of the person throwing the bag will move.

Correct Answer: B

Solution:

When one person throws a bag to the other, both will experience forces due to the action and reaction principle. As a result, both carts will move away from each other.

(mv)^2

mv^2

\frac{1}{2} mv^2

mv

Correct Answer: D

Solution:

Momentum is calculated as the product of mass and velocity, which is

mv

Conservation of mass

Newton's First Law of Motion

Conservation of momentum

Newton's Second Law of Motion

Correct Answer: C

Solution:

The movement of the carts illustrates the conservation of momentum. As the sandbag is thrown, the momentum is transferred, causing the carts to move in opposite directions.

500 N

1000 N

1500 N

2000 N

Correct Answer: A

Solution:

The force exerted can be calculated using the formula:

F = \frac{\Delta p}{\Delta t}

, where

\Delta p = m \cdot \Delta v

. Here,

m = 0.01 \text{ kg}

\Delta v = 150 \text{ m/s}

, and

\Delta t = 0.03 \text{ s}

. Thus,

F = \frac{0.01 \times 150}{0.03} = 500 \text{ N}

The forces cancel each other out.

The truck has too much inertia.

The person is not applying enough force.

The truck is on a frictionless surface.

Correct Answer: B

Solution:

The truck does not move because it has a large mass, and thus a large inertia, which resists changes in its state of motion.

It remains the same

It is halved

It is doubled

It is quadrupled

Correct Answer: C

Solution:

Momentum is directly proportional to velocity. If the velocity is doubled, the momentum is also doubled.

10 N

20 N

30 N

40 N

Correct Answer: B

Solution:

The force can be calculated using Newton's second law,

F = ma

. First, calculate the acceleration using

a = \frac{v_f - v_i}{t} = \frac{6 - 2}{4} = 1 \text{ m/s}^2

. Then,

F = 10 \times 1 = 10 \text{ N}

1.67 m/s

2 m/s

3 m/s

5 m/s

Correct Answer: A

Solution:

Using conservation of momentum, the total momentum before collision is equal to the total momentum after collision.

m_1v_1 + m_2v_2 = (m_1 + m_2)v

. Thus,

1 \times 10 + 5 \times 0 = (1 + 5)v

, solving gives

v = 1.67 \text{ m/s}

Conservation of energy

Newton's First Law of Motion

Newton's Third Law of Motion

Conservation of mass

Correct Answer: C

Solution:

The action of throwing the bag causes an equal and opposite reaction, demonstrating Newton's Third Law of Motion.

250 N/m

200 N/m

300 N/m

150 N/m

Correct Answer: A

Solution:

Using Hooke's Law,

F = kx

, where

F = 50 \text{ N}

and

x = 0.2 \text{ m}

. Solving for

k

gives

k = \frac{F}{x} = \frac{50}{0.2} = 250 \text{ N/m}

The boat moves towards the dock.

The boat remains stationary.

The boat moves away from the dock.

The boat sinks.

Correct Answer: C

Solution:

According to Newton's Third Law of Motion, for every action, there is an equal and opposite reaction. As the person jumps towards the dock, the boat moves in the opposite direction, away from the dock.

1 kg m/s

2 kg m/s

3 kg m/s

5 kg m/s

Correct Answer: C

Solution:

Initial momentum

p_i = 0.2 \times 15 = 3 \text{ kg m/s}

. Final momentum

p_f = 0.2 \times (-10) = -2 \text{ kg m/s}

. Change in momentum

\Delta p = p_f - p_i = -2 - 3 = -5 \text{ kg m/s}

. Magnitude is 5 kg m/s.

0.2 m/s

0.4 m/s

0.5 m/s

1 m/s

Correct Answer: A

Solution:

Using conservation of momentum, initial momentum is zero. After throwing,

50 \times v_1 + 5 \times 2 = 0

. Solving gives

v_1 = -0.2 \text{ m/s}

. The other cart moves with the same speed in the opposite direction.

1 J

2 J

0.5 J

10 J

Correct Answer: A

Solution:

The potential energy stored in a spring is given by

PE = \frac{1}{2} k x^2

, where

k

is the spring constant and

x

is the compression.

PE = \frac{1}{2} \times 200 \times (0.1)^2 = 1

The block continues to move at a constant velocity.

The block comes to a stop immediately.

The block accelerates indefinitely.

The block moves in the opposite direction.

Correct Answer: A

Solution:

According to Newton's First Law, an object in motion will stay in motion with the same velocity unless acted upon by an unbalanced force.

The coin moves with the card.

The coin remains on the card.

The coin falls into the glass tumbler.

The coin flies off in the opposite direction.

Correct Answer: C

Solution:

Due to inertia, the coin remains in its state of rest and falls vertically into the glass when the card is flicked away.

5 m/s

6.25 m/s

7.5 m/s

8 m/s

Correct Answer: B

Solution:

Using the conservation of momentum, the total momentum before collision equals the total momentum after collision.

m_1v_1 + m_2v_2 = (m_1 + m_2)v

. Here,

m_1 = 5 \text{ kg}

v_1 = 10 \text{ m/s}

m_2 = 3 \text{ kg}

v_2 = 0

. Thus,

5 \times 10 + 3 \times 0 = (5 + 3)v

. Solving for

v

v = \frac{50}{8} = 6.25 \text{ m/s}

Inertia is the tendency of an object to resist a change in its state of motion.

Inertia is the force that acts on an object to change its motion.

Inertia is the energy required to move an object.

Inertia is the speed at which an object moves.

Correct Answer: A

Solution:

Inertia is the natural tendency of an object to resist a change in its state of motion or rest.

The truck

The car

Both have the same inertia

Inertia is not related to mass

Correct Answer: A

Solution:

Inertia is directly related to mass. The truck, being more massive, has more inertia.

Due to the friction between the car and the road.

Because of the inertia of the passengers.

Because the car accelerates.

Due to the gravitational pull.

Correct Answer: B

Solution:

The tendency of passengers to continue in their straight-line motion while the car turns is due to inertia.

50 N

500 N

750 N

1500 N

Correct Answer: B

Solution:

The force exerted can be calculated using the formula

F = \frac{\Delta p}{\Delta t}

, where

\Delta p

is the change in momentum. The initial momentum is

mv = 0.01 \times 150 = 1.5 \text{ kg m/s}

and the final momentum is 0. Thus,

\Delta p = 1.5 \text{ kg m/s}

. The force is

F = \frac{1.5}{0.03} = 50 \text{ N}

It will stop immediately.

It will continue moving to the right.

It will move to the left.

It will move in a circular path.

Correct Answer: B

Solution:

According to Newton's First Law of Motion, the block will continue moving in the same direction unless acted upon by another force.

400 N

800 N

1000 N

2000 N

Correct Answer: B

Solution:

The change in momentum

\Delta p = m(v_f - v_i) = 0.01 \times (0 - 200) = -2 \text{ kg m/s}

. The force is

F = \frac{\Delta p}{\Delta t} = \frac{-2}{0.05} = -40 \text{ N}

Solution:

This is an example of Newton's Third Law of Motion. When the bullet is propelled forward by the explosive force, the gun experiences an equal and opposite recoil force.

Force and Laws of Motion

Learning Objectives

Learning Objectives

Revision Notes & Summary

Chapter 8: Force and Laws of Motion

Introduction

Concept of Force

Newton's Laws of Motion

First Law of Motion

Second Law of Motion

Third Law of Motion

Activities to Illustrate Concepts

Important Diagrams

Diagram 8.1

Diagram 8.2

Diagram 8.6

Diagram 8.9

Summary of Key Points

Exam Tips & Common Mistakes

Common Mistakes and Exam Tips

Common Pitfalls

Exam Tips

AI Learning Assistant

Practice Test – MCQs, True/False

Multiple Choice Questions

Q1.A hockey ball of mass 200 g is struck by a hockey stick, changing its velocity from 10 m/s to -5 m/s (opposite direction). What is the magnitude of the change in momentum of the hockey ball?

Correct Answer: A

Q2.A hockey ball of mass 200 g moving at 10 m/s is struck to return along its original path with a velocity of 5 m/s. What is the magnitude of the change in momentum?

Correct Answer: A

Q3.Why do some leaves get detached from a tree when we vigorously shake its branch?

Correct Answer: B

Q4.A block of mass 2 kg is placed on a frictionless horizontal surface and connected to a spring with a spring constant of 150 N/m. The spring is initially compressed by 0.2 m. What is the potential energy stored in the spring?

Correct Answer: B

Q5.A bullet of mass 20 g is fired from a gun with a velocity of 300 m/s. If the bullet penetrates a wooden block and comes to rest in 0.05 seconds, what is the magnitude of the average force exerted by the block on the bullet?

Correct Answer: B

Q6.If a hockey ball of mass 200 g is struck by a hockey stick and returns along its original path with a velocity of 5 m/s, what is the change in velocity if it was initially moving at 10 m/s?

Correct Answer: B

Q7.A block of mass 2 kg is placed on a frictionless horizontal surface. A force of 10 N is applied to the block. What will be the acceleration of the block?

Correct Answer: B

Q8.A container with a spring inside is compressed by a force of 50 N, and the spring constant is 250 N/m. What is the compression distance of the spring?

Correct Answer: B

Q9.A block on a table is pushed with a force of 10 N to the right, while a frictional force of 4 N acts to the left. What is the net force acting on the block?

Correct Answer: A

Q10.If a bullet of mass 10 g is fired from a gun with a velocity of 150 m/s, what is the recoil velocity of the gun if its mass is 2 kg?

Correct Answer: A

Q11.According to Newton's Third Law of Motion, when a gun is fired, the bullet is propelled forward and the gun experiences a recoil. What is the direction of the recoil force on the gun?

Correct Answer: B

Q12.A person is jumping from a boat to a dock while holding a rope. What happens to the boat as the person jumps?

Correct Answer: C

Q13.A 100 kg object is accelerated uniformly from rest to a velocity of 10 m/s in 5 seconds. What is the work done on the object?

Correct Answer: C

Q14.In a physics experiment, a hand flicks a card from under a coin resting on a cup. What principle is demonstrated when the coin falls into the cup?

Correct Answer: B

Q15.If a force of 200 N is applied horizontally to move a wooden cabinet at constant velocity, what is the friction force exerted on the cabinet?

Correct Answer: C

Q16.According to Newton's First Law of Motion, what is required to change the state of motion of an object?

Correct Answer: B

Q17.A person jumps from a boat towards a dock. According to Newton's Third Law of Motion, what happens to the boat?

Correct Answer: C

Q18.A 10 g bullet is fired from a gun with a velocity of 200 m/s. If the gun has a mass of 2 kg, what is the recoil velocity of the gun?

Correct Answer: A

Q19.Why does a train have more inertia than a small cart?

Correct Answer: B

Q20.A person jumps from a boat to a dock while holding a rope. If the person has a mass of 60 kg and jumps with a velocity of 3 m/s towards the dock, what will be the velocity of the boat (mass 120 kg) moving in the opposite direction due to the action-reaction forces?

Correct Answer: C

Q21.Two people are standing on separate carts facing each other. If one person throws a bag to the other, what will happen to the carts?

Correct Answer: B

Q22.A hockey ball of mass 200 g is travelling at 10 m/s and is struck to return along its original path with a velocity of 5 m/s. What is the magnitude of the change in momentum?

Correct Answer: A

Q23.Which of the following has more inertia?

Correct Answer: B

Q24.Why do you fall in the forward direction when a moving bus brakes to a stop?

Correct Answer: B

Q25.Which of the following scenarios best illustrates Newton's First Law of Motion?

Correct Answer: B

Q26.In a physics experiment, a block of mass 2 kg is placed on a frictionless inclined plane making an angle of 30° with the horizontal. What is the acceleration of the block down the incline?

Correct Answer: A

Q27.What happens to a coin placed on a card when the card is flicked away quickly?

Correct Answer: B

Q28.A block is placed on a table and a force is applied to move it from position X to Y. If the force applied is equal to the frictional force, what will be the block's motion?