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Questions and Answers
Which law of motion states that when one object exerts a force on another object, the second object instantaneously exerts a force back on the first?
Which law of motion states that when one object exerts a force on another object, the second object instantaneously exerts a force back on the first?
In the context of the text, what does the negative sign in '-0.0004 N' imply about the force?
In the context of the text, what does the negative sign in '-0.0004 N' imply about the force?
What is the term used to describe the two opposing forces that are equal in magnitude but opposite in direction as per the third law of motion?
What is the term used to describe the two opposing forces that are equal in magnitude but opposite in direction as per the third law of motion?
In the scenario involving spring balances, what does it mean when both balances show the same readings on their scales?
In the scenario involving spring balances, what does it mean when both balances show the same readings on their scales?
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When two players collide during a football game, what physical principle explains why both feel hurt?
When two players collide during a football game, what physical principle explains why both feel hurt?
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What does the unit of force, newton, represent?
What does the unit of force, newton, represent?
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In the context of physics, the second law of motion relates force to:
In the context of physics, the second law of motion relates force to:
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How does a fielder catching a fast-moving cricket ball illustrate the concept of force?
How does a fielder catching a fast-moving cricket ball illustrate the concept of force?
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Which physical quantity is represented by the symbol 'N'?
Which physical quantity is represented by the symbol 'N'?
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What does the rate of change of momentum represent?
What does the rate of change of momentum represent?
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According to the third law of motion, when a force is applied on an object, the object __________.
According to the third law of motion, when a force is applied on an object, the object __________.
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When a gun is fired, the recoil of the gun is caused by __________.
When a gun is fired, the recoil of the gun is caused by __________.
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If a sailor jumps out of a rowing boat, the boat will __________.
If a sailor jumps out of a rowing boat, the boat will __________.
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If two objects have different masses and an equal force is applied to them, __________.
If two objects have different masses and an equal force is applied to them, __________.
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When you start walking on a road, the force that accelerates you forward is __________.
When you start walking on a road, the force that accelerates you forward is __________.
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What physical quantity combines an object's mass and velocity?
What physical quantity combines an object's mass and velocity?
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In the context of motion, what is the equivalent of a push or pull on an object?
In the context of motion, what is the equivalent of a push or pull on an object?
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When a fast-moving cricket ball hits a spectator, what determines the impact produced?
When a fast-moving cricket ball hits a spectator, what determines the impact produced?
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What property of an object was introduced by Newton to describe the product of its mass and velocity?
What property of an object was introduced by Newton to describe the product of its mass and velocity?
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How does the impact produced by objects relate to their mass and velocity?
How does the impact produced by objects relate to their mass and velocity?
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Why do we tend to fall backwards when a bus suddenly starts moving?
Why do we tend to fall backwards when a bus suddenly starts moving?
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How does a motorcar making a sharp turn at high speed relate to the law of inertia?
How does a motorcar making a sharp turn at high speed relate to the law of inertia?
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In terms of physics, what causes a person to slip to one side of the seat when a motorcar changes its direction?
In terms of physics, what causes a person to slip to one side of the seat when a motorcar changes its direction?
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Why do objects tend to remain at rest unless acted upon by an unbalanced force?
Why do objects tend to remain at rest unless acted upon by an unbalanced force?
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How does removing the bottom carom coin from a pile illustrate inertia?
How does removing the bottom carom coin from a pile illustrate inertia?
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According to Newton's third law of motion, when a sailor jumps forward in a boat, the force exerted by the sailor on the boat and the force exerted by the boat on the sailor are:
According to Newton's third law of motion, when a sailor jumps forward in a boat, the force exerted by the sailor on the boat and the force exerted by the boat on the sailor are:
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In the activity described, if two children of equal mass stand on separate carts and throw a bag of sand towards each other, which of the following statements is true?
In the activity described, if two children of equal mass stand on separate carts and throw a bag of sand towards each other, which of the following statements is true?
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If a gun is fired horizontally, which of the following statements is correct regarding the recoil of the gun?
If a gun is fired horizontally, which of the following statements is correct regarding the recoil of the gun?
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According to Newton's second law of motion, if the net force acting on an object is doubled, and its mass is also doubled, what will happen to its acceleration?
According to Newton's second law of motion, if the net force acting on an object is doubled, and its mass is also doubled, what will happen to its acceleration?
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In the activity described, if two children of different masses stand on separate carts and throw bags of sand with the same force, which of the following statements is true?
In the activity described, if two children of different masses stand on separate carts and throw bags of sand with the same force, which of the following statements is true?
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What does a sudden decrease in velocity of a ball indicate about the rate of change of momentum?
What does a sudden decrease in velocity of a ball indicate about the rate of change of momentum?
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Why do athletes in a high jump event land on cushioned or sand beds?
Why do athletes in a high jump event land on cushioned or sand beds?
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How is the first law of motion mathematically related to the second law of motion?
How is the first law of motion mathematically related to the second law of motion?
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What happens to an object when no force is applied and its initial and final velocities are equal?
What happens to an object when no force is applied and its initial and final velocities are equal?
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In physics, what is the meaning of recoil?
In physics, what is the meaning of recoil?
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In the context of physics, what does a large force applied to hold a catch suggest?
In the context of physics, what does a large force applied to hold a catch suggest?
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How do cushioned beds help reduce the force experienced by athletes in high jump events?
How do cushioned beds help reduce the force experienced by athletes in high jump events?
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"If u is zero then v will also be zero." This statement refers to an object that is:
"If u is zero then v will also be zero." This statement refers to an object that is:
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What changes if a constant force acts on an object for a longer duration?
What changes if a constant force acts on an object for a longer duration?
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How does landing on a cushioned bed affect the time of an athlete's fall?
How does landing on a cushioned bed affect the time of an athlete's fall?
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Acceleration is directly proportional to the change in velocity over time.
Acceleration is directly proportional to the change in velocity over time.
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The unit of force in the SI system is joule.
The unit of force in the SI system is joule.
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If the mass of an object doubles and its acceleration remains constant, then the force acting on the object has doubled.
If the mass of an object doubles and its acceleration remains constant, then the force acting on the object has doubled.
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The constant 'k' in the equation F = km × (v - u) represents the value of acceleration.
The constant 'k' in the equation F = km × (v - u) represents the value of acceleration.
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The second law of motion provides a method to measure force by multiplying mass and acceleration.
The second law of motion provides a method to measure force by multiplying mass and acceleration.
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The SI unit of force is kilogram meter per second squared.
The SI unit of force is kilogram meter per second squared.
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A force of one newton can produce an acceleration of 1 m/s^2 on an object of mass 2 kg.
A force of one newton can produce an acceleration of 1 m/s^2 on an object of mass 2 kg.
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The momentum of an object is the product of its mass and velocity, and has a direction opposite to that of the velocity.
The momentum of an object is the product of its mass and velocity, and has a direction opposite to that of the velocity.
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The third law of motion states that every action has an unequal and opposite reaction that act on the same body.
The third law of motion states that every action has an unequal and opposite reaction that act on the same body.
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If there is no unbalanced force acting on an object, the object will continue to move with a constant velocity.
If there is no unbalanced force acting on an object, the object will continue to move with a constant velocity.
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It is possible for an object with an acceleration of $-0.02$ m/s² to have a negative force exerted on it.
It is possible for an object with an acceleration of $-0.02$ m/s² to have a negative force exerted on it.
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According to Newton's third law of motion, the two spring balances connected together will always show different readings on their scales.
According to Newton's third law of motion, the two spring balances connected together will always show different readings on their scales.
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Acceleration and velocity are directly proportional according to Newton's second law of motion.
Acceleration and velocity are directly proportional according to Newton's second law of motion.
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In physics, the unit of force 'newton' represents the mass of an object.
In physics, the unit of force 'newton' represents the mass of an object.
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The rate of change of velocity indicates how quickly an object's direction changes.
The rate of change of velocity indicates how quickly an object's direction changes.
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Acceleration is directly proportional to the net external force and inversely proportional to the mass of an object, as per Newton's second law of motion.
Acceleration is directly proportional to the net external force and inversely proportional to the mass of an object, as per Newton's second law of motion.
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If two objects have the same mass and one is accelerated at 5 m/s² while the other is accelerated at 2 m/s², they will experience the same force of acceleration.
If two objects have the same mass and one is accelerated at 5 m/s² while the other is accelerated at 2 m/s², they will experience the same force of acceleration.
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When calculating the force required to accelerate a 4 kg mass at 3 m/s², the force obtained would be less than 15 N.
When calculating the force required to accelerate a 4 kg mass at 3 m/s², the force obtained would be less than 15 N.
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If a 500 kg car accelerates at 2 m/s², the force exerted by the car's engine would be 1000 N.
If a 500 kg car accelerates at 2 m/s², the force exerted by the car's engine would be 1000 N.
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The unit of force, newton, is defined as one joule per kilogram per second squared.
The unit of force, newton, is defined as one joule per kilogram per second squared.
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A force is directly proportional to the acceleration of an object, according to Newton's second law of motion.
A force is directly proportional to the acceleration of an object, according to Newton's second law of motion.
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Acceleration is the rate of change of position with respect to time.
Acceleration is the rate of change of position with respect to time.
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The unit of force, newton, is defined as 1 kgm/s^2.
The unit of force, newton, is defined as 1 kgm/s^2.
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In the absence of a force, an object's velocity will always remain constant.
In the absence of a force, an object's velocity will always remain constant.
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Force and acceleration are always in opposite directions when acting on an object.
Force and acceleration are always in opposite directions when acting on an object.
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A force acting in the same direction as the motion of an object always increases its speed.
A force acting in the same direction as the motion of an object always increases its speed.
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Balanced forces result in a change in the state of rest or motion of an object.
Balanced forces result in a change in the state of rest or motion of an object.
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If two opposite forces of different magnitudes act on a block, the block will move in the direction of the smaller force.
If two opposite forces of different magnitudes act on a block, the block will move in the direction of the smaller force.
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Acceleration is directly proportional to the rate of change of velocity over time.
Acceleration is directly proportional to the rate of change of velocity over time.
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The unit of force in the SI system is kilogram-meter per second squared.
The unit of force in the SI system is kilogram-meter per second squared.
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Acceleration is inversely proportional to the time rate at which momentum is changed.
Acceleration is inversely proportional to the time rate at which momentum is changed.
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The SI unit of momentum is kilogram-metre per second.
The SI unit of momentum is kilogram-metre per second.
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The change of momentum of an object is only determined by the magnitude of the force, not the time during which the force is exerted.
The change of momentum of an object is only determined by the magnitude of the force, not the time during which the force is exerted.
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A sudden push (unbalanced force) always results in immediate acceleration of an object.
A sudden push (unbalanced force) always results in immediate acceleration of an object.
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The second law of motion states that the rate of change of momentum of an object is not proportional to the applied unbalanced force.
The second law of motion states that the rate of change of momentum of an object is not proportional to the applied unbalanced force.
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Force necessary to change the momentum of an object does not depend on the time rate at which the momentum is changed.
Force necessary to change the momentum of an object does not depend on the time rate at which the momentum is changed.
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If the net force acting on an object is doubled and its mass is halved, its acceleration will also be halved.
If the net force acting on an object is doubled and its mass is halved, its acceleration will also be halved.
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The initial and final momentum of an object are always equal.
The initial and final momentum of an object are always equal.
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The force necessary to change the momentum of an object does not depend on how long the force is applied.
The force necessary to change the momentum of an object does not depend on how long the force is applied.
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Acceleration remains constant when a constant force acts on an object for a longer duration.
Acceleration remains constant when a constant force acts on an object for a longer duration.
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Define the term 'acceleration' and how is it related to velocity?
Define the term 'acceleration' and how is it related to velocity?
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Explain the relationship between force and acceleration according to Newton's second law of motion.
Explain the relationship between force and acceleration according to Newton's second law of motion.
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What is the SI unit of force and how is it defined?
What is the SI unit of force and how is it defined?
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How is the rate of change of momentum related to the applied force on an object?
How is the rate of change of momentum related to the applied force on an object?
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In the context of physics, explain the relationship between acceleration and velocity over time.
In the context of physics, explain the relationship between acceleration and velocity over time.
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Explain the relationship between force and change in momentum according to Newton's second law of motion.
Explain the relationship between force and change in momentum according to Newton's second law of motion.
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How does the acceleration of an object relate to the rate at which its momentum is changed?
How does the acceleration of an object relate to the rate at which its momentum is changed?
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Describe the SI unit of force and its mathematical representation.
Describe the SI unit of force and its mathematical representation.
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Explain the significance of the rate of change of velocity in relation to an object's motion.
Explain the significance of the rate of change of velocity in relation to an object's motion.
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What does the unit of momentum, kilogram-meter per second (kg m/s), signify in the context of Newton's laws of motion?
What does the unit of momentum, kilogram-meter per second (kg m/s), signify in the context of Newton's laws of motion?
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Explain how the rate of change of momentum of an object is affected by the time interval during which the force is applied.
Explain how the rate of change of momentum of an object is affected by the time interval during which the force is applied.
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How does the duration of force application affect the final velocity of an object according to Newton's second law of motion?
How does the duration of force application affect the final velocity of an object according to Newton's second law of motion?
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What is the mathematical relationship between acceleration and velocity according to Newton's second law of motion?
What is the mathematical relationship between acceleration and velocity according to Newton's second law of motion?
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How is force related to mass and acceleration as per Newton's second law of motion?
How is force related to mass and acceleration as per Newton's second law of motion?
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Explain the significance of units in the equation F = ma.
Explain the significance of units in the equation F = ma.
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What is the magnitude of the force exerted by the brakes on a motorcar if its initial velocity is 30 m/s, final velocity is 0 m/s, total mass is 1000 kg, and the time taken to stop is 4 seconds?
What is the magnitude of the force exerted by the brakes on a motorcar if its initial velocity is 30 m/s, final velocity is 0 m/s, total mass is 1000 kg, and the time taken to stop is 4 seconds?
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If a force of 5 N gives a mass of 10 kg an acceleration of 10 m/s², and a mass of 20 kg an acceleration of 20 m/s², what acceleration would it give if both masses were tied together?
If a force of 5 N gives a mass of 10 kg an acceleration of 10 m/s², and a mass of 20 kg an acceleration of 20 m/s², what acceleration would it give if both masses were tied together?
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What acceleration does a ball experience if its initial velocity is 20 cm/s and it comes to a stop in 10 seconds due to frictional force exerted by the table?
What acceleration does a ball experience if its initial velocity is 20 cm/s and it comes to a stop in 10 seconds due to frictional force exerted by the table?
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What is the acceleration of an object if it experiences a change in velocity of 30 m/s in 5 seconds?
What is the acceleration of an object if it experiences a change in velocity of 30 m/s in 5 seconds?
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If a force of 100 N is applied to an object with a mass of 20 kg, what is the resulting acceleration?
If a force of 100 N is applied to an object with a mass of 20 kg, what is the resulting acceleration?
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How does the impact produced by objects depend on their mass and velocity?
How does the impact produced by objects depend on their mass and velocity?
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What physical quantity combines an object's mass and velocity?
What physical quantity combines an object's mass and velocity?
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What does the negative sign in '-0.0004 N' imply about the force?
What does the negative sign in '-0.0004 N' imply about the force?
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How is the unit of force, newton, defined?
How is the unit of force, newton, defined?
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What does the rate of change of momentum represent?
What does the rate of change of momentum represent?
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Explain the concept of an unbalanced force and its role in the acceleration of an object.
Explain the concept of an unbalanced force and its role in the acceleration of an object.
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Describe how Galileo's observations on objects on an inclined plane relate to Newton's first law of motion.
Describe how Galileo's observations on objects on an inclined plane relate to Newton's first law of motion.
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What is the significance of an object moving with uniform velocity in the absence of any external force?
What is the significance of an object moving with uniform velocity in the absence of any external force?
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Explain the relationship between acceleration and velocity in terms of Newton's second law of motion.
Explain the relationship between acceleration and velocity in terms of Newton's second law of motion.
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What does the unit of force, newton, represent and how is it defined?
What does the unit of force, newton, represent and how is it defined?
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What force is required to accelerate a 4 kg mass at 3 m/s²?
What force is required to accelerate a 4 kg mass at 3 m/s²?
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If a motorcar takes 4 seconds to stop after brakes are applied with a mass of 1000 kg, what force is exerted by the brakes?
If a motorcar takes 4 seconds to stop after brakes are applied with a mass of 1000 kg, what force is exerted by the brakes?
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What is the final velocity of an object if a force of 10 N is applied for 2 seconds to a mass of 5 kg?
What is the final velocity of an object if a force of 10 N is applied for 2 seconds to a mass of 5 kg?
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If a 2 kg mass is accelerated at 5 m/s² and a 4 kg mass is accelerated at 2 m/s², which requires a greater force?
If a 2 kg mass is accelerated at 5 m/s² and a 4 kg mass is accelerated at 2 m/s², which requires a greater force?
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What acceleration does a combined mass of 0.75 kg experience when a 5 N force is applied?
What acceleration does a combined mass of 0.75 kg experience when a 5 N force is applied?
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If a gun is fired and the recoil of the gun occurs, what physical principle explains this recoil?
If a gun is fired and the recoil of the gun occurs, what physical principle explains this recoil?
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Explain the relationship between force and acceleration according to Newton's second law of motion.
Explain the relationship between force and acceleration according to Newton's second law of motion.
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What is the SI unit of force and how is it defined?
What is the SI unit of force and how is it defined?
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How does acceleration relate to the rate of change of velocity over time?
How does acceleration relate to the rate of change of velocity over time?
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What property of an object was introduced by Newton to describe the product of its mass and velocity?
What property of an object was introduced by Newton to describe the product of its mass and velocity?
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The rate of change of momentum is proportional to mass times (___ - ___)
The rate of change of momentum is proportional to mass times (___ - ___)
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Acceleration is the rate of change of ___
Acceleration is the rate of change of ___
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The SI unit of force is ___
The SI unit of force is ___
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The value of constant 'k' becomes 1 when the unit of force is defined as producing an acceleration of 1 m/s² in an object of 1 ___ mass
The value of constant 'k' becomes 1 when the unit of force is defined as producing an acceleration of 1 m/s² in an object of 1 ___ mass
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The impact of catching a fast moving ball is reduced by increasing the time during which the high velocity of the moving ball decreases to ___
The impact of catching a fast moving ball is reduced by increasing the time during which the high velocity of the moving ball decreases to ___
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In Newton's second law of motion, force is mathematically represented as F = __ * a
In Newton's second law of motion, force is mathematically represented as F = __ * a
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Acceleration is directly proportional to the rate of change of __ over time
Acceleration is directly proportional to the rate of change of __ over time
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The SI unit of force, newton, is defined as 1 kgm/s^2. It is represented by the symbol __
The SI unit of force, newton, is defined as 1 kgm/s^2. It is represented by the symbol __
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A sudden decrease in velocity of a ball indicates a large rate of change of __
A sudden decrease in velocity of a ball indicates a large rate of change of __
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The rate of change of momentum is related to the applied __ on an object
The rate of change of momentum is related to the applied __ on an object
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The SI unit of momentum is kilogram-metre per second (kg m s-1). The rate of change of momentum of an object is proportional to the applied unbalanced force in the direction of force. This statement is a direct implication of __________'s second law of motion.
The SI unit of momentum is kilogram-metre per second (kg m s-1). The rate of change of momentum of an object is proportional to the applied unbalanced force in the direction of force. This statement is a direct implication of __________'s second law of motion.
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Acceleration is directly proportional to the rate of change of velocity over time. This relationship is described by __________'s second law of motion.
Acceleration is directly proportional to the rate of change of velocity over time. This relationship is described by __________'s second law of motion.
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The unit of force in the SI system is kilogram-meter per second squared, also known as the __________.
The unit of force in the SI system is kilogram-meter per second squared, also known as the __________.
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The force necessary to change the momentum of an object depends not only on the magnitude of the force but also on the __________ during which the force is exerted.
The force necessary to change the momentum of an object depends not only on the magnitude of the force but also on the __________ during which the force is exerted.
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Acceleration is directly proportional to the change in velocity over time. This relationship is defined by __________'s second law of motion.
Acceleration is directly proportional to the change in velocity over time. This relationship is defined by __________'s second law of motion.
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The total mass of the motorcar along with its passengers = 1000 kg and the time taken to stop the motorcar, t = 4 s. From Eq.(8.5) we have the magnitude of the force (F) applied by the brakes as m(v – u)/t. On substituting the values, we get F = 1000 kg × (0 – 30) m s-1/4 s = – 7500 kg m s-2 or – 7500 N. The negative sign tells us that the force exerted by the brakes is ______ to the direction of motion of the motorcar.
The total mass of the motorcar along with its passengers = 1000 kg and the time taken to stop the motorcar, t = 4 s. From Eq.(8.5) we have the magnitude of the force (F) applied by the brakes as m(v – u)/t. On substituting the values, we get F = 1000 kg × (0 – 30) m s-1/4 s = – 7500 kg m s-2 or – 7500 N. The negative sign tells us that the force exerted by the brakes is ______ to the direction of motion of the motorcar.
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Due to the frictional force exerted by the table, the velocity of the ball decreases down to zero in 10 s. Thus, u = 20 cm s–1; v = 0 cm s-1 and t = 10 s. Since the velocity-time graph is a straight line, it is clear that the ball moves with a constant ______. The acceleration a is v −u t = (0 cm s-1 – 20 cm s-1)/10 s = –2 cm s-2 = –0.02 m s-2.
Due to the frictional force exerted by the table, the velocity of the ball decreases down to zero in 10 s. Thus, u = 20 cm s–1; v = 0 cm s-1 and t = 10 s. Since the velocity-time graph is a straight line, it is clear that the ball moves with a constant ______. The acceleration a is v −u t = (0 cm s-1 – 20 cm s-1)/10 s = –2 cm s-2 = –0.02 m s-2.
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Example 8.4 A force of 5 N gives a mass m1, an acceleration of 10 m s–2 and a mass m2, an acceleration of 20 m s-2. What acceleration would it give if both the masses were ______ together?
Example 8.4 A force of 5 N gives a mass m1, an acceleration of 10 m s–2 and a mass m2, an acceleration of 20 m s-2. What acceleration would it give if both the masses were ______ together?
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From Eq.(8.5) we have the magnitude of the force (F) applied by the brakes as m(v – u)/t. On substituting the values, we get F = 1000 kg × (0 – 30) m s-1/4 s = – 7500 kg m s-2 or – 7500 N. The negative sign tells us that the force exerted by the brakes is ______ to the direction of motion of the motorcar.
From Eq.(8.5) we have the magnitude of the force (F) applied by the brakes as m(v – u)/t. On substituting the values, we get F = 1000 kg × (0 – 30) m s-1/4 s = – 7500 kg m s-2 or – 7500 N. The negative sign tells us that the force exerted by the brakes is ______ to the direction of motion of the motorcar.
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The initial velocity of the ball is 20 cm s-1. Due to the frictional force exerted by the table, the velocity of the ball decreases down to zero in 10 s. Thus, u = 20 cm s–1; v = 0 cm s-1 and t = 10 s. Since the velocity-time graph is a straight line, it is clear that the ball moves with a constant ______.
The initial velocity of the ball is 20 cm s-1. Due to the frictional force exerted by the table, the velocity of the ball decreases down to zero in 10 s. Thus, u = 20 cm s–1; v = 0 cm s-1 and t = 10 s. Since the velocity-time graph is a straight line, it is clear that the ball moves with a constant ______.
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According to Newton's second law of motion, the momentum of an object is the product of its mass and ______.
According to Newton's second law of motion, the momentum of an object is the product of its mass and ______.
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In physics, force is directly proportional to the ______ of an object.
In physics, force is directly proportional to the ______ of an object.
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The SI unit of force, newton, is defined as one joule per kilogram per second squared, where a joule represents a unit of ______.
The SI unit of force, newton, is defined as one joule per kilogram per second squared, where a joule represents a unit of ______.
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The rate of change of momentum is proportional to mass times ______.
The rate of change of momentum is proportional to mass times ______.
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The impact of catching a fast moving ball is reduced by increasing the time during which the high velocity of the moving ball decreases to ______.
The impact of catching a fast moving ball is reduced by increasing the time during which the high velocity of the moving ball decreases to ______.
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An object moves with a uniform velocity when the forces acting on the object are balanced and there is no net external force on it. If an unbalanced force is applied on the object, there will be a change either in its speed or in the direction of its motion. Thus, to accelerate the motion of an object, an unbalanced force is required. And the change in its speed (or in the direction of motion) would continue as long as this unbalanced force is applied. However, if this force is __________, the object would continue to move with the velocity it has acquired till then.
An object moves with a uniform velocity when the forces acting on the object are balanced and there is no net external force on it. If an unbalanced force is applied on the object, there will be a change either in its speed or in the direction of its motion. Thus, to accelerate the motion of an object, an unbalanced force is required. And the change in its speed (or in the direction of motion) would continue as long as this unbalanced force is applied. However, if this force is __________, the object would continue to move with the velocity it has acquired till then.
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By observing the motion of objects on an inclined plane, Galileo deduced that objects move with a constant speed when no force acts on them. He observed that when a marble rolls down an inclined plane, its velocity increases. In the next chapter, you will learn that the marble falls under the unbalanced force of gravity as it rolls down and attains a definite velocity by the time it reaches the bottom. Its velocity decreases when it climbs up. Galileo argued that when the marble is released from left, it would roll down the slope and go up on the opposite side to the same height from which it was released. Galileo's observations highlight the relationship between _________, speed, and direction of motion.
By observing the motion of objects on an inclined plane, Galileo deduced that objects move with a constant speed when no force acts on them. He observed that when a marble rolls down an inclined plane, its velocity increases. In the next chapter, you will learn that the marble falls under the unbalanced force of gravity as it rolls down and attains a definite velocity by the time it reaches the bottom. Its velocity decreases when it climbs up. Galileo argued that when the marble is released from left, it would roll down the slope and go up on the opposite side to the same height from which it was released. Galileo's observations highlight the relationship between _________, speed, and direction of motion.
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When no force acts on an object, it moves with a constant speed. However, to change this speed and accelerate the object, an __________ force is required to be applied.
When no force acts on an object, it moves with a constant speed. However, to change this speed and accelerate the object, an __________ force is required to be applied.
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The first law of motion states that objects move with a constant speed when no force acts on them. This implies that an object at rest will stay at rest and an object in motion will continue moving with the same speed and direction unless acted upon by an __________ force.
The first law of motion states that objects move with a constant speed when no force acts on them. This implies that an object at rest will stay at rest and an object in motion will continue moving with the same speed and direction unless acted upon by an __________ force.
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Acceleration is the rate of change of velocity. When an object is subjected to a force, it accelerates in the direction of that force. Therefore, acceleration is directly proportional to the __________ applied on an object.
Acceleration is the rate of change of velocity. When an object is subjected to a force, it accelerates in the direction of that force. Therefore, acceleration is directly proportional to the __________ applied on an object.
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The force necessary to change the momentum of an object is directly proportional to the ______ of the object.
The force necessary to change the momentum of an object is directly proportional to the ______ of the object.
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Acceleration is the rate of change of ______.
Acceleration is the rate of change of ______.
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According to Newton's second law of motion, a force is directly proportional to the ______ of an object.
According to Newton's second law of motion, a force is directly proportional to the ______ of an object.
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The SI unit of force, newton, is defined as 1 kgm/s^2. It is represented by the symbol __.
The SI unit of force, newton, is defined as 1 kgm/s^2. It is represented by the symbol __.
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The rate of change of momentum is proportional to mass times (___ - ___).
The rate of change of momentum is proportional to mass times (___ - ___).
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Acceleration and velocity are directly proportional according to Newton's second law of motion.
Acceleration and velocity are directly proportional according to Newton's second law of motion.
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Acceleration is directly proportional to the rate of change of ______ over time.
Acceleration is directly proportional to the rate of change of ______ over time.
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The impact of catching a fast moving ball is reduced by increasing the time during which the high velocity of the moving ball decreases to ___
The impact of catching a fast moving ball is reduced by increasing the time during which the high velocity of the moving ball decreases to ___
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Why do athletes in a high jump event land on cushioned or sand beds?
Why do athletes in a high jump event land on cushioned or sand beds?
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In the activity described, if two children of different masses stand on separate carts and throw bags of sand with the same force, which of the following statements is true?
In the activity described, if two children of different masses stand on separate carts and throw bags of sand with the same force, which of the following statements is true?
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