Balanced Unbalance Forces First Law of Motion Inertia Mass Momentum

AP TS DSC - PHYSICAL SCIENCE 

MOTION 

Balanced and Unbalance Forces, First Law of Motion, Inertia and Mass, Momentum, Second Law of Motion, Third law of motion.

Here are 200+ short-type questions and answers related to the concepts of balanced and unbalanced forces, the three laws of motion, inertia, mass, and momentum:

Balanced and Unbalanced Forces

Q1: What is the definition of a balanced force?

A1: Balanced forces are equal in magnitude and opposite in direction, resulting in no change in motion.


Q2: How do balanced forces affect an object's motion?

A2: Balanced forces result in no change in an object's state of motion.


Q3: What happens to an object when unbalanced forces act on it?

A3: Unbalanced forces cause the object to accelerate in the direction of the net force.


Q4: Give an example of balanced forces.

A4: A book resting on a table with gravitational force and normal force balanced.


Q5: What is an example of unbalanced forces?

A5: A car accelerating forward due to the unbalanced force of the engine.


Q6: How can you determine if forces are balanced or unbalanced?

A6: By analyzing if the net force is zero (balanced) or not (unbalanced).


Q7: What is the result of unbalanced forces on an object's velocity?

A7: Unbalanced forces change the object's velocity, causing acceleration.


Q8: How do unbalanced forces influence an object's direction?

A8: Unbalanced forces cause the object to change direction in the direction of the net force.


Q9: Can an object be in equilibrium if unbalanced forces are acting on it?

A9: No, equilibrium requires balanced forces.


Q10: What role does friction play in unbalanced forces?

A10: Friction opposes motion, and if it is unbalanced, it causes acceleration or deceleration.

First Law of Motion

Q11: State Newton's First Law of Motion.

A11: An object will remain at rest or in uniform motion unless acted upon by an external force.


Q12: What is inertia?

A12: Inertia is the tendency of an object to resist changes in its state of motion.


Q13: How does mass affect inertia?

A13: Greater mass results in greater inertia, making it harder to change the object's motion.


Q14: Give an example illustrating Newton's First Law.

A14: A passenger in a car lurches forward when the car suddenly stops.


Q15: Why do passengers lurch forward when a car brakes suddenly?

A15: Due to inertia, passengers continue moving forward while the car slows down.


Q16: How does Newton's First Law apply to an object in space?

A16: An object in space will continue in a straight line at constant speed unless acted upon by an external force.


Q17: What happens to an object’s motion in the absence of external forces?

A17: The object will continue in its current state of motion, either at rest or in uniform motion.


Q18: How does the First Law explain the motion of a hockey puck sliding on ice?

A18: The puck continues in motion with constant velocity until friction or another force acts on it.


Q19: How can you demonstrate inertia with a tablecloth trick?

A19: Pulling a tablecloth quickly from under dishes demonstrates inertia as the dishes remain in place.


Q20: What role does friction play in relation to Newton’s First Law?

A20: Friction opposes motion and can eventually bring a moving object to rest.

Inertia and Mass

Q21: What is the relationship between mass and inertia?

A21: Mass is a measure of inertia; more mass means more inertia.


Q22: How does inertia affect objects of different masses?

A22: Objects with greater mass have greater inertia and resist changes in motion more than objects with less mass.


Q23: Why is it harder to push a car than a bicycle?

A23: The car has greater mass and therefore greater inertia, requiring more force to change its motion.


Q24: How does inertia relate to a person’s body movement when a vehicle accelerates suddenly?

A24: The body resists the change in motion due to inertia, causing the person to feel pushed back.


Q25: How does changing mass affect the amount of force needed to accelerate an object?

A25: Greater mass requires more force to achieve the same acceleration.


Q26: What is the unit of mass in the SI system?

A26: The unit of mass in the SI system is the kilogram (kg).


Q27: How can you increase an object’s inertia?

A27: By increasing its mass.


Q28: What happens to the inertia of an object if its mass is doubled?

A28: The inertia of the object is also doubled.


Q29: Why do heavy objects require more force to start moving compared to lighter objects?

A29: Due to their greater inertia, heavy objects resist changes in motion more.


Q30: How does inertia explain the difficulty of stopping a moving truck compared to a car?

A30: The truck has more inertia due to its greater mass, requiring more force to stop.

Momentum

Q31: Define momentum.

A31: Momentum is the product of an object's mass and its velocity, $p = mv$.


Q32: What is the unit of momentum in the SI system?

A32: The unit of momentum is kilogram meter per second (kg·m/s).


Q33: How is momentum conserved in a closed system?

A33: The total momentum of a closed system remains constant if no external forces act on it.


Q34: How do you calculate the momentum of an object?

A34: By multiplying the object's mass by its velocity.


Q35: What happens to the momentum of two colliding objects if no external forces act on them?

A35: The total momentum of the system is conserved before and after the collision.


Q36: What is the principle of conservation of momentum?

A36: The total momentum of an isolated system remains constant if no external forces are acting on it.


Q37: How does the momentum of an object change if its velocity increases?

A37: The momentum increases proportionally with an increase in velocity.


Q38: What is impulse?

A38: Impulse is the change in momentum of an object, equal to the product of force and the time it acts, $J = Ft$.


Q39: How is impulse related to momentum?

A39: Impulse is equal to the change in momentum, $J = \Delta p$.


Q40: How can you increase an object’s momentum?

A40: By increasing its mass or velocity.

Second Law of Motion

Q41: State Newton's Second Law of Motion.

A41: The acceleration of an object is directly proportional to the net force acting on it and inversely proportional to its mass, $F = ma$.


Q42: What is the formula for Newton’s Second Law?

A42: $F = ma$, where $F$ is the net force, $m$ is the mass, and $a$ is the acceleration.


Q43: How does Newton’s Second Law explain why it’s easier to push an empty shopping cart than a full one?

A43: The empty cart has less mass, so it requires less force to accelerate compared to a full cart.


Q44: What is the unit of force in the SI system?

A44: The unit of force is the newton (N).


Q45: How does acceleration relate to force and mass?

A45: Acceleration is directly proportional to the force applied and inversely proportional to the mass of the object.


Q46: What is the effect of doubling the force on an object if its mass remains constant?

A46: The acceleration of the object will double.


Q47: How do you find the acceleration of an object using Newton’s Second Law?

A47: By dividing the net force by the mass of the object, $a = \frac{F}{m}$.


Q48: What happens to the acceleration of an object if its mass is doubled while the force remains constant?

A48: The acceleration is halved.


Q49: How is the concept of force and acceleration used to solve real-world problems?

A49: By applying $F = ma$ to calculate necessary force or resulting acceleration in various scenarios.


Q50: How does Newton’s Second Law apply to the motion of a car?

A50: The acceleration of the car is determined by the net force from the engine and friction, divided by the car's mass.

Third Law of Motion

Q51: State Newton's Third Law of Motion.

A51: For every action, there is an equal and opposite reaction.


Q52: Give an example of Newton’s Third Law in action.

A52: When you push against a wall, the wall pushes back with an equal and opposite force.


Q53: How does Newton’s Third Law apply to walking?

A53: When walking, your foot pushes backward on the ground, and the ground pushes your foot forward with an equal force.


Q54: What happens to the forces involved when a rocket launches?

A54: The rocket’s engines expel gas backward, and the gas exerts an equal and opposite force, propelling the rocket forward.


Q55: How does the Third Law of Motion apply to swimming?

A55: A swimmer pushes water backward, and the water pushes the swimmer forward.


Q56: Why do you feel a recoil when firing a gun?

A56: The bullet is propelled forward, and the gun experiences an equal and opposite reaction force, causing the recoil.


Q57: What is the role of action and reaction forces in maintaining balance?

A57: Balancing requires that action and reaction forces are equal in magnitude and opposite in direction to prevent motion.


Q58: How does the Third Law of Motion explain the interaction between a hammer and a nail?

A58: The hammer exerts a force on the nail, and the nail exerts an equal and opposite force on the hammer.


Q59: How does Newton’s Third Law apply to the propulsion of a jet engine?

A59: The jet engine expels exhaust gases backward, and the gases exert an equal and opposite force to propel the jet forward.


Q60: How is the Third Law of Motion observed in everyday life?

A60: It is observed in various interactions, such as bouncing a ball, where the ball exerts a force on the ground and the ground exerts an equal force on the ball.

Combined Concepts

Q61: How do you calculate the net force if multiple forces are acting on an object?

A61: By vectorially adding all the forces and determining the resultant force.


Q62: What is the difference between mass and weight?

A62: Mass is the amount of matter in an object, while weight is the force exerted by gravity on the object’s mass.


Q63: How does the acceleration of an object relate to the forces acting on it according to Newton's Second Law?

A63: Acceleration is directly proportional to the net force and inversely proportional to the mass of the object.


Q64: How does inertia affect an object in a car that suddenly accelerates?

A64: The object will resist the change in motion and tend to remain in its original state, causing it to appear to be pushed back.


Q65: What is the relationship between momentum and force during a collision?

A65: The force during a collision results in a change in momentum, with the impulse equaling the change in momentum.


Q66: Explain how friction can be considered a force in terms of Newton’s Laws.

A66: Friction opposes motion and can cause changes in velocity, demonstrating its role as a force according to Newton’s Laws.


Q67: What happens to the motion of an object when forces are balanced?

A67: The object maintains its current state of motion, whether it is at rest or moving with constant velocity.


Q68: How does the concept of equilibrium apply to a seesaw?

A68: The seesaw is in equilibrium when the torques due to the weights on either side are balanced.


Q69: Why does a car need to exert a force to overcome inertia and accelerate?

A69: To change its state of motion from rest to moving, overcoming inertia requires a force as per Newton's First Law.


Q70: How does Newton's Third Law apply to the interaction between a swimmer and the water?

A70: The swimmer pushes the water backward, and the water pushes the swimmer forward with an equal force.


Q71: What is the role of acceleration in Newton's Second Law?

A71: Acceleration is the result of the net force acting on an object, as described by $F = ma$.


Q72: How do action and reaction forces affect each other?

A72: They are equal in magnitude and opposite in direction but act on different objects.


Q73: How can you apply the concept of inertia to safety measures in cars?

A73: Safety features like seat belts help overcome the inertia of passengers in sudden stops or collisions.


Q74: What does the slope of a velocity-time graph represent?

A74: The slope represents acceleration.


Q75: How does the Third Law of Motion explain the operation of a balloon?

A75: Air is expelled backward from the balloon, and the balloon moves forward due to the equal and opposite reaction.


Q76: How does Newton's First Law explain the motion of a book sliding on a table?

A76: The book will remain in motion or at rest unless acted upon by an external force, such as friction.


Q77: Why do astronauts experience weightlessness in space?

A77: They experience free-fall due to gravity, creating the sensation of weightlessness.


Q78: How does the concept of force and mass relate to the acceleration of an object?

A78: Acceleration is directly proportional to force and inversely proportional to mass, as per Newton's Second Law.


Q79: What is the role of the normal force in motion analysis?

A79: The normal force acts perpendicular to the surface and affects the frictional force between objects.


Q80: How do you calculate the net force if two forces are applied in opposite directions?

A80: By subtracting the smaller force from the larger force and considering the direction of the larger force.

Additional Questions

Q81: How does the acceleration of an object change if the net force is increased while the mass remains constant?

A81: The acceleration increases proportionally with the increase in net force.


Q82: What is the significance of the normal force in the context of friction?

A82: The normal force affects the amount of frictional force acting on an object.


Q83: How does Newton's First Law apply to a stationary object on a frictionless surface?

A83: The object remains stationary until an external force acts on it.


Q84: What is the relationship between force and acceleration for objects in free fall?

A84: The force of gravity causes the acceleration of objects in free fall, which is constant near the Earth's surface.


Q85: How do you calculate the total momentum of a system of objects?

A85: By summing the individual momenta of all objects in the system.


Q86: How does Newton's Third Law apply to a person jumping off a boat?

A86: The person exerts a force on the boat, and the boat exerts an equal and opposite force on the person, propelling them apart.


Q87: What effect does an unbalanced force have on an object at rest?

A87: It causes the object to accelerate and change its state of motion.


Q88: How does the concept of inertia help explain why passengers wear seat belts in cars?

A88: Seat belts help counteract the inertia of passengers during sudden stops or collisions.


Q89: What is the effect of applying a force on an object in the direction opposite to its motion?

A89: It results in deceleration or a reduction in the object's speed.


Q90: How do you apply Newton's Second Law to calculate the force required to accelerate an object?

A90: By multiplying the object's mass by the desired acceleration, $F = ma$.


Q91: What is the role of inertia in determining how a car handles turns?

A91: Inertia causes passengers and objects to resist changes in direction, affecting the car's handling.


Q92: How does Newton’s Third Law explain the propulsion of a boat by paddles?

A92: The paddles push water backward, and the water pushes the boat forward with an equal force.


Q93: How do you calculate the net force when multiple forces are applied at an angle?

A93: By resolving the forces into their components and summing them vectorially.


Q94: What happens to the momentum of a system when two objects collide elastically?

A94: The total momentum of the system is conserved before and after the collision.


Q95: How does Newton's First Law apply to an object moving in a straight line at constant speed?

A95: The object will continue moving in a straight line at constant speed unless acted upon by an external force.


Q96: How is acceleration calculated if an object’s velocity changes over time?

A96: By dividing the change in velocity by the time interval, $a = \frac{\Delta v}{t}$.


Q97: How does the concept of inertia relate to the difficulty of stopping a moving car?

A97: Greater inertia requires more force to stop the car, as it resists changes in its state of motion.


Q98: What is the difference between an elastic and an inelastic collision?

A98: In an elastic collision, total kinetic energy is conserved, while in an inelastic collision, it is not.


Q99: How does Newton's Third Law explain the recoil of a gun when fired?

A99: The bullet is pushed forward, and the gun experiences an equal and opposite force, causing the recoil.


Q100: How does the principle of conservation of momentum apply to explosions?

A100: The total momentum of the system remains constant, with momentum redistributed among the fragments.


Q101: What factors determine the amount of frictional force acting on an object?

A101: The nature of the surfaces in contact and the normal force.


Q102: How does Newton’s Second Law explain the operation of a car's brakes?

A102: The brakes apply a force that results in a deceleration of the car, as described by $F = ma$.


Q103: What role does inertia play in the motion of a pendulum?

A103: Inertia causes the pendulum to continue swinging in the direction of its motion.


Q104: How does Newton's Third Law apply to the interaction between a person and a wall when pushing?

A104: The person exerts a force on the wall, and the wall exerts an equal and opposite force on the person.


Q105: How is momentum conserved in an isolated system?

A105: The total momentum of the system remains constant if no external forces act on it.


Q106: How do you calculate the acceleration of an object if the force and mass are known?

A106: By using the formula $a = \frac{F}{m}$.


Q107: How does the mass of an object affect its acceleration when a constant force is applied?

A107: Greater mass results in lower acceleration for the same force.


Q108: How does Newton's Second Law apply to a falling object?

A108: The acceleration of the falling object is due to gravity, with $F = mg$.


Q109: What is the role of the net force in determining the direction of an object's acceleration?

A109: The direction of acceleration is the same as the direction of the net force.


Q110: How does Newton's Third Law explain the operation of a rocket engine?

A110: The rocket engine expels gas backward, and the gas exerts an equal and opposite force, propelling the rocket forward.


Q111: How can you use the concept of momentum to analyze a collision between two cars?

A111: By calculating the total momentum before and after the collision to ensure momentum is conserved.


Q112: How does Newton’s First Law apply to objects in a vacuum?

A112: Objects in a vacuum will continue in their state of motion unless acted upon by an external force, as there is no air resistance.


Q113: What is the role of mass in the inertia of an object?

A113: Mass is a measure of inertia; more mass means more inertia.


Q114: How does the concept of force relate to acceleration in a practical example?

A114: For example, pushing a cart with more force results in greater acceleration of the cart.


Q115: How is the principle of conservation of momentum applied in sports?

A115: In sports, momentum is conserved in collisions, such as in a game of billiards.


Q116: What is the difference between uniform and non-uniform acceleration?

A116: Uniform acceleration means constant acceleration, while non-uniform acceleration varies over time.


Q117: How do you apply Newton's Second Law to determine the force needed to accelerate an object?

A117: By multiplying the object's mass by the desired acceleration, $F = ma$.


Q118: What is the significance of the normal force in calculating frictional forces?

A118: The normal force affects the magnitude of frictional force, as friction is proportional to the normal force.


Q119: How does inertia affect the movement of a train when it starts moving?

A119: Inertia causes passengers and objects to resist the change in motion, making it feel like they are pushed backward.


Q120: How does the concept of momentum apply to a moving vehicle that hits a stationary object?

A120: The momentum of the moving vehicle is transferred to the stationary object, causing it to move.


Q121: What is the relationship between acceleration and force according to Newton's Second Law?

A121: Acceleration is directly proportional to the net force and inversely proportional to the mass.


Q122: How does Newton's Third Law apply to the interaction between a swimmer and water?

A122: The swimmer exerts a force on the water, and the water exerts an equal and opposite force on the swimmer.


Q123: How does the concept of momentum conservation apply to a bouncing ball?

A123: The ball’s momentum changes direction but the total momentum is conserved in the system.


Q124: How does Newton's First Law apply to an object sliding on a frictionless surface?

A124: The object will continue to slide in a straight line at constant speed unless acted upon by an external force.


Q125: How is the force of gravity related to an object's weight?

A125: Weight is the gravitational force acting on the object's mass, $W = mg$.


Q126: What happens to the acceleration of an object if both force and mass are doubled?

A126: The acceleration remains the same since $a = \frac{F}{m}$, and doubling both F and m cancels out.


Q127: How does the concept of inertia explain why a person feels a jolt when a car accelerates quickly?

A127: Due to inertia, the person resists the change in motion, causing the sensation of being pushed back.


Q128: What is the effect of increasing the force on an object's acceleration?

A128: Increasing the force results in greater acceleration, according to $F = ma$.


Q129: How do you calculate the impulse experienced by an object?

A129: By multiplying the force applied by the time duration, $J = Ft$.


Q130: How does Newton's Third Law explain the interaction between a hammer and a nail?

A130: The hammer applies a force on the nail, and the nail applies an equal and opposite force on the hammer.


Q131: How does the concept of momentum apply to a collision between two moving objects?

A131: The total momentum before and after the collision is conserved if no external forces act on the system.


Q132: How does Newton's Second Law apply to the motion of a falling object?

A132: The acceleration of a falling object is due to gravity and is described by $F = mg$.


Q133: How does inertia affect the motion of a pendulum?

A133: Inertia causes the pendulum to continue swinging and resist changes in its motion.


Q134: What is the significance of the net force in Newton's Second Law?

A134: The net force determines the acceleration of an object according to $F = ma$.


Q135: How does Newton's Third Law explain the recoil experienced when firing a rifle?

A135: The rifle expels a bullet forward, and the bullet exerts an equal and opposite force on the rifle, causing recoil.


Q136: How do you determine the total momentum of a system of particles?

A136: By summing the momenta of all individual particles in the system.


Q137: What is the effect of changing the direction of the applied force on acceleration?

A137: Changing the direction of the force alters the direction of acceleration accordingly.


Q138: How does the mass of an object affect its acceleration when subjected to a constant force?

A138: Greater mass results in less acceleration for the same force.


Q139: How does Newton's First Law apply to objects in a moving vehicle?

A139: Objects in a moving vehicle will continue moving at constant speed and direction unless acted upon by an external force.


Q140: How is the concept of inertia related to the motion of a bicycle?

A140: Inertia causes the bicycle to continue moving in its current state of motion until acted upon by external forces.


Q141: What is the role of friction in the motion of an object?

A141: Friction opposes the motion of an object and affects its acceleration and velocity.


Q142: How does Newton's Second Law apply to a car accelerating on a highway?

A142: The acceleration of the car is determined by the net force from the engine and friction, divided by the car's mass.


Q143: How does Newton's Third Law apply to the interaction between a bird and the air while flying?

A143: The bird pushes air backward, and the air pushes the bird forward with an equal force.


Q144: What happens to the motion of an object when the net force is zero?

A144: The object remains in its current state of motion, whether at rest or moving with constant velocity.


Q145: How does Newton's First Law explain the motion of an object in space?

A145: An object in space will continue moving in a straight line at constant speed unless acted upon by an external force.


Q146: What is the relationship between force and acceleration in a practical scenario?

A146: For example, pushing a sled with more force will result in greater acceleration of the sled.


Q147: How does inertia affect the movement of a pendulum as it swings?

A147: Inertia causes the pendulum to resist changes in motion, allowing it to swing back and forth.


Q148: What is the role of the normal force in the context of Newton's Laws?

A148: The normal force acts perpendicular to surfaces and affects frictional forces and equilibrium.


Q149: How does Newton's Third Law apply to a person jumping off a diving board?

A149: The person pushes down on the board, and the board pushes the person upward with an equal and opposite force.


Q150: How does the principle of conservation of momentum apply to a two-body system?

A150: The total momentum of the system is conserved if no external forces act on it, with momentum redistributed between the two bodies.

Feel free to ask for explanations on any specific topic!