Action Reaction Forces - Middle School Physical Science

Identify whether "weight on a book" and "normal on the book" are an action–reaction pair.

No; both forces act on the book. Action-reaction pairs must act on different objects, not the same one.
Identify the action–reaction pair when a foot kicks a soccer ball: what force pairs with foot on ball?

Ball on foot. Ball pushes back on foot with equal force.
If object A pushes object B to the east, what is the direction of Bs force on A?

West. Action-reaction forces are always in opposite directions.
If a small car hits a large truck, which statement is correct about the collision forces?

They are equal in magnitude and opposite in direction. Newton's Third Law applies regardless of object masses or sizes.
What law states that forces between two interacting objects are equal in size and opposite in direction?

Newton's Third Law of Motion. States that every action has an equal and opposite reaction.
Identify the actionreaction pair: a soccer player kicks a ball.

Foot on ball; ball on foot. The foot applies force to the ball, and the ball applies equal force back.
Identify the actionreaction pair: a hockey puck hits the boards.

Puck on boards; boards on puck. During impact, puck and boards exert equal forces on each other.
Which force is the reaction to "the ball pushes on the wall" during a bounce?

The wall pushes on the ball. Newton's third law: ball's push has equal and opposite reaction from wall.
If a ball exerts $25\ \text{N}$ downward on the floor at impact, what does the floor exert on the ball?

$25\ \text{N}$ upward on the ball. Floor pushes back with equal force in opposite direction.
Choose the correct action–reaction pair: (A) normal and weight on a book (B) book on table and table on book.

B. Only B shows forces between two objects; A shows forces on same object.
What two features must an action–reaction force pair always have?

Equal magnitude and opposite direction. Action-reaction pairs are always equal in size but opposite in direction.
Which statement is always true for an action–reaction pair: same object or different objects?

Different objects. Newton's third law requires forces act on separate objects.
If object A exerts $30\ \text{N}$ on object B, what is the magnitude of B's force on A?

$30\ \text{N}$ . Action-reaction forces always have equal magnitudes.
Identify the action-reaction pair: two ice skaters push off each other.

Skater A on skater B; skater B on skater A. Each skater pushes the other with equal force.
A person jumps and pushes down on the ground. Which force is the reaction force?

The ground pushing up on the person. Ground pushes up to propel the jumper upward.
A rocket pushes exhaust gases backward. Identify the reaction force on the rocket.

Exhaust gases push rocket forward. Gases push rocket opposite to their motion.
Identify the action–reaction pair: a skateboarder's foot pushes backward on the ground.

Foot on ground; ground on foot. Foot pushes ground back; ground pushes foot forward.
Identify the action–reaction pair: two ice skaters push off each other with their hands.

Skater A on skater B; skater B on skater A. Push forces between people are equal and opposite by Newton's third law.
A swimmer pushes water backward. Identify the reaction force on the swimmer.

Water pushes swimmer forward. Water reacts by pushing swimmer in opposite direction.
Which option names a correct actionreaction pair in a collision: A) friction & normal B) wall on ball & ball on wall?

B) wall on ball & ball on wall. Option B shows forces on different objects; A shows unrelated force types.
What two objects must be named to identify an action-reaction pair in a collision?

The two interacting objects (object A and object B). Action-reaction pairs always involve forces between two specific objects.
Which statement is correct in a collision: (A) heavier object exerts larger force, (B) forces are equal and opposite?

Option B. Newton's third law: forces equal regardless of mass difference.
Identify the action–reaction pair when a car rear-ends a truck: what force pairs with car on truck?

Truck on car. Truck exerts equal force back on car during impact.
Which statement is always true about the directions of forces in an action–reaction pair?

They are opposite directions. Newton's third law requires paired forces to point in opposite directions.
What must be true about the objects involved in an action–reaction force pair?

They are two different interacting objects. Action-reaction pairs always involve two separate objects.
Identify the action–reaction pair when a bat hits a baseball.

Bat on ball; ball on bat. The bat exerts force on ball while ball exerts equal force back on bat.
In a collision, if object $A$ exerts $50\ \text{N}$ on object $B$ , what is $|\vec{F}_{B\to A}|$ ?

$50\ \text{N}$ . Action-reaction forces always have equal magnitudes by Newton's third law.
Find the action-reaction pair for "Earth pulls on a falling apple."

Apple pulls on Earth. By Newton's third law, apple also pulls Earth with equal gravitational force.
Identify the reaction force: A bat exerts a force on a ball during a hit.

The ball exerts a force on the bat. By Newton's third law, the ball pushes back on the bat with equal force.
What is always true about directions in an action-reaction pair during a collision?

They point in opposite directions. Action-reaction forces always point in opposite directions along the same line.
Identify the action-reaction pair when two carts collide and stick together.

Cart 1 on cart 2; cart 2 on cart 1. During collision, each cart exerts equal and opposite forces on the other.
Which pair is an action–reaction pair: (A) friction and normal on one box, or (B) box on floor and floor on box?

B: box on floor and floor on box. Action-reaction pairs involve two objects, not forces on one object.
What law states that forces in an interaction occur in equal and opposite pairs?

Newton's third law of motion. States that every action has an equal and opposite reaction.
A ball hits a wall. Identify the action–reaction pair using correct "on" wording.

Wall on ball; ball on wall. Each object exerts a force on the other during the collision.
In a collision, which object has the larger acceleration: the one with smaller mass or larger mass?

The one with smaller mass. Equal forces cause different accelerations due to $F=ma$ .
Which option is an action-reaction pair: A) normal+weight on one box, B) car on truck+truck on car?

B) car on truck and truck on car. Option A shows forces on same object; B shows forces between two objects.
Identify the action-reaction pair when a car rear-ends a truck.

Car on truck; truck on car. Both vehicles push on each other with equal force.
Identify the action-reaction pair when two billiard balls collide (ball A and ball B).

A on B; B on A. Each ball exerts equal and opposite forces on the other during contact.
Identify the correct force-pair rule: forces act on the same object or on different objects?

They act on different objects. Each force in the pair acts on a separate object.
In a hockey stick–puck collision, identify the reaction force to "stick exerts force on puck."

Puck exerts force on stick. Equal and opposite reaction per Newton's third law.
What two features must an action–reaction force pair always have?

Equal magnitude and opposite direction. Action-reaction pairs are always equal in size but point in opposite directions.
If object A exerts $30\,\text{N}$ on object B, what is the force of B on A?

$30\,\text{N}$ in the opposite direction. Newton's third law: equal magnitude, opposite direction.
Identify the action-reaction pair when a car rear-ends a truck.

Car on truck; truck on car. Each vehicle exerts equal force on the other during collision.
In a bat–ball collision, identify the reaction force to "bat pushes on ball."

Ball pushes on bat. Newton's third law: equal and opposite forces.
Identify the action–reaction pair when a bowling ball hits a pin.

Ball on pin; pin on ball. The pin exerts an equal force back on the ball.
What is the relationship between the types of forces in an action-reaction pair (contact, gravitational, etc.)?

They are the same type of force. Both forces must be the same type (e.g., both contact or both gravitational).
Identify the actionreaction pair: a bat hits a baseball during contact.

Bat on ball; ball on bat. The bat pushes the ball, and the ball pushes back on the bat equally.
What law states that forces between two interacting objects are equal in magnitude and opposite in direction?

Newtons Third Law of Motion. States that for every action, there is an equal and opposite reaction.
What is an action–reaction force pair in a collision?

Two equal and opposite forces on two different objects. Each object exerts a force on the other during contact.
In a car–wall collision, identify the reaction force to "car pushes on wall."

Wall pushes on car. Equal and opposite force per Newton's third law.
Which statement is correct: "Action happens first" or "action and reaction occur at the same time"?

Action and reaction occur at the same time. Forces in a pair exist simultaneously, not sequentially.
What is always true about the directions of forces in an action-reaction pair?

They are opposite in direction. Action-reaction forces point in opposite directions.
Identify the action-reaction pair when two ice skaters push off each other.

Skater 1 on skater 2; skater 2 on skater 1. Each skater pushes the other with equal force in opposite directions.
What is the action-reaction pair for the gravitational force between Earth and a falling apple?

Earth pulls apple; apple pulls Earth. Gravity creates mutual attraction between both objects.
Which statement is always true for an action-reaction pair: $F_{A\to B}$ and $F_{B\to A}$ ?

$F_{A\to B}=-F_{B\to A}$ . Mathematical expression of Newton's third law showing equal and opposite forces.
Identify the actionreaction pair: a hammer strikes a nail.

Hammer on nail; nail on hammer. The hammer pushes the nail, and the nail pushes back equally.
Identify the action-reaction pair when a soccer player kicks a soccer ball.

Foot on ball; ball on foot. The foot applies force to ball, and ball applies equal force to foot.
What law states that forces in an interaction come in equal and opposite pairs?

Newton's third law of motion. States that for every action, there's an equal and opposite reaction.
Which option is an actionreaction pair: A) weight & normal B) tire on road & road on tire?

B) tire on road & road on tire. Option B shows forces on different objects; A shows forces on the same object.
If object A exerts $50\,\text{N}$ on object B, what is the magnitude of the force B exerts on A?

$50\,\text{N}$ . Newton's third law: forces are always equal in magnitude.
What is an action–reaction force pair in a collision between two objects?

Two forces on different objects, equal and opposite. Each object exerts a force on the other during contact.
Identify the action–reaction pair: a car rear-ends a truck; focus on contact forces only.

Car on truck; truck on car. Collision forces are equal regardless of object masses.
Identify the action-reaction pair: a hand catches a thrown ball.

Hand on ball; ball on hand. The ball pushes back on the hand during deceleration.
Identify the action-reaction pair when a bat hits a baseball.

Bat on ball; ball on bat. The bat exerts force on ball, and ball exerts equal force back on bat.
What must be true about the objects in an action-reaction pair: same object or different objects?

They act on different objects. Action-reaction pairs never act on the same object.
Which pair is an action–reaction pair: "friction on box by floor" and which matching force?

Friction on floor by box. Friction forces between surfaces form action-reaction pairs.
Which option is the reaction force to "wall pushes on your hand" when you punch a wall?

Your hand pushes on wall. The reaction acts on the wall, completing the force pair.
If $\vec{F}_{A\to B}$ points east, what direction does $\vec{F}_{B\to A}$ point?

West. Reaction force points in opposite direction.
Identify the reaction to "Earth pulls on a falling apple" (a noncontact interaction).

Apple pulls on Earth. Gravity works both ways: the apple also pulls on Earth with equal force.
What law states that forces in an interaction come in equal and opposite pairs?

Newton's third law of motion. States that for every action, there's an equal and opposite reaction.
Find the action–reaction pair: "Earth pulls on the ball" during a fall. What is the partner force?

The ball pulls on Earth. Gravity pairs: Earth pulls ball, ball pulls Earth.
What is the reaction force to "the floor pushes up on a dropped book" at impact?

The book pushes down on the floor. The book exerts equal downward force on impact.
Choose the correct pair for a book resting on a table: A) weight+normal B) book on table+table on book.

B) Book on table; table on book. Action-reaction pairs involve forces between objects, not forces on one object.
Identify the action–reaction pair when two ice skaters push off each other.

Skater 1 on skater 2; skater 2 on skater 1. Each skater pushes the other with equal force.
What is the most important rule for identifying an action–reaction pair in a collision?

The forces act on two different objects. One force acts on each object - never both forces on the same object.
Which statement is always true for an action–reaction pair: same object or different objects?

Different objects. Newton's third law requires action-reaction forces to act on separate objects.
During contact, if the forces are equal, why can accelerations be different for the two objects?

Different masses cause different accelerations: $a=\frac{F}{m}$ . Newton's second law: same force gives smaller mass larger acceleration.
If $\vec{F}_{A\to B}$ points east during a collision, what direction does $\vec{F}_{B\to A}$ point?

West. Action-reaction forces always point in opposite directions.
Which force is the reaction to "the wall pushes on the ball" during a bounce?

The ball pushes on the wall. Newton's third law: wall's push has equal and opposite reaction from ball.
Identify the reaction force to "hand pulls on rope" during a tug-of-war.

Rope pulls on hand. The rope pulls back with equal force.
Identify the action force: A ball exerts a force on a bat during a hit.

The bat exerts a force on the ball. The bat's push on the ball pairs with the ball's push on the bat.
What is the reaction force to "object A pushes on object B" in a collision?

Object B pushes on object A. Newton's third law: forces always come in equal and opposite pairs.
What law states that forces in an interaction come in equal and opposite pairs?

Newton's third law of motion. States that for every action force, there's an equal and opposite reaction force.
Which option is an action-reaction pair: A) friction+normal on same object B) tire on road+road on tire?

B) Tire on road; road on tire. Action-reaction pairs act on different objects; A has forces on same object.
Identify the action-reaction pair when a foot kicks a soccer ball.

Foot on ball; ball on foot. Foot pushes ball forward; ball pushes foot backward with equal force.
Identify the reaction force to "Earth pulls on an apple (gravity)" while it falls.

Apple pulls on Earth (gravity). Gravitational forces between objects are mutual and equal.
Identify the action-reaction pair when a bowling ball hits a pin.

Ball on pin; pin on ball. Pin pushes back on ball with equal force during impact.
Identify the action-reaction pair when a bowling ball hits a pin.

Ball on pin; pin on ball. Ball strikes pin with force; pin strikes ball back with equal force.
Identify the action–reaction pair: a bat hits a baseball during a collision.

Bat on ball; ball on bat. Bat exerts force on ball; ball exerts equal force back on bat.
A ball hits a wall. Which force is the reaction to the wall pushing on the ball?

The ball pushing on the wall. Ball exerts equal force on wall during impact.
Identify the action-reaction pair when a book rests on a table (normal force interaction).

Table on book; book on table. Table pushes up on book (normal force), book pushes down on table.
Which option is an action-reaction pair: A) friction and normal B) car on truck and truck on car?

B) car on truck and truck on car. Option B shows forces between two objects; A shows forces on same object.
Choose the correct pair: Is the reaction to "Earth pulls on apple" equal to "apple pulls on Earth"?

Yes, "apple pulls on Earth" is the reaction force. Gravity pairs: Earth-apple forces are equal and opposite.
Two carts collide. Identify the reaction force to "cart $1$ pushes on cart $2$ ."

Cart $2$ pushes on cart $1$ . Equal and opposite force on the other cart.
What is the correct equation form for an action–reaction pair between objects $A$ and $B$ ?

$\vec{F}_{A\to B}=-\vec{F}_{B\to A}$ . The negative sign shows the forces point in opposite directions.
Identify the action–reaction pair when a hammer strikes a nail: what force pairs with hammer on nail?

Nail on hammer. Nail pushes back on hammer with equal force.
Identify the actionreaction pair: a bowling ball collides with a pin.

Ball on pin; pin on ball. During impact, the ball and pin exert equal forces on each other.
Identify the action-reaction pair: a bowling ball collides with a pin.

Ball on pin; pin on ball. During collision, each object exerts force on the other.
In a collision, which two forces form an action–reaction pair: normal forces or friction forces?

The contact (normal) forces between the two objects. Contact forces during collision form the pair.
What is the reaction force to "Object A pushes on Object B" in a collision?

Object B pushes on Object A. Newton's third law: if A acts on B, then B acts on A with equal and opposite force.
What law states that forces between two interacting objects come in equal and opposite pairs?

Newton's Third Law of Motion. States that forces always come in equal and opposite pairs between interacting objects.
If a truck hits a small car, which object exerts the larger force during the collision?

Neither; the forces are equal in magnitude. Newton's Third Law applies regardless of object size or mass.
Which statement is correct about action-reaction forces during a collision: they cancel or they do not cancel?

They do not cancel because they act on different objects. Forces on different objects can't cancel each other.
Identify the action-reaction pair: a puck hits the boards in hockey.

Puck on boards; boards on puck. The boards push back on the puck with equal force.
In a hammer–nail collision, identify the reaction force to "hammer pushes on nail."

Nail pushes on hammer. The nail pushes back with equal force.
Identify the key rule about objects for an action–reaction force pair.

They act on two different objects. Action-reaction forces never act on the same object, always on different ones.
What does the equality in Newton's third law mean for an interaction: $F_{A\rightarrow B}$ and $F_{B\rightarrow A}$ ?

$F_{A\rightarrow B} = -F_{B\rightarrow A}$ . Forces are equal in magnitude but opposite in direction (negative sign).
Identify the key rule about objects in an action-reaction pair: same object or different objects?

Different objects. Action-reaction pairs always act on two different objects, never the same one.
In a collision, do action–reaction forces cancel each other to give zero net force on one object?

No; they act on different objects. Forces can't cancel because they act on separate objects.
Find the action–reaction pair in this statement: "Truck pushes car forward; car speeds up."

Truck pushes car; car pushes truck. Action-reaction pair involves mutual forces between truck and car.
Identify the action–reaction pair when a soccer player kicks a ball.

Foot on ball; ball on foot. The ball pushes back on the foot with equal force.
Two ice skaters push apart. Which force is the reaction to skater A pushing on skater B?

Skater B pushing on skater A. B pushes A with equal force when A pushes B.
Identify the actionreaction pair: a hand slaps a tabletop.

Hand on table; table on hand. The hand pushes the table, and the table pushes back on the hand.
If a small cart collides with a large cart, which statement about forces is correct?

Each cart experiences equal-magnitude opposite forces. Newton's third law applies regardless of mass differences between objects.
Identify the key rule about objects for an action-reaction force pair.

They act on two different objects. Action-reaction forces never act on the same object - always on different objects.
Identify the action-reaction pair when a hockey puck hits the boards.

Puck on boards; boards on puck. Puck pushes boards; boards push puck with equal force.
Which option is an action–reaction pair: (A) friction and normal on one box, (B) box on floor and floor on box?

Option B. Option A has both forces on one object; B shows forces on different objects.
What law states that forces in an interaction come in equal and opposite pairs?

Newton's Third Law of Motion. States that for every action force, there's an equal and opposite reaction force.
What is the correct equation form for an action–reaction pair between objects $A$ and $B$ ?

$\vec{F}_{A\to B}=-\vec{F}_{B\to A}$ . Shows forces are equal in magnitude but opposite in direction.
Which statement is always true for an action–reaction pair: equal forces or equal accelerations?

Equal forces. Forces are always equal; accelerations depend on mass.
What two features must an action-reaction force pair always have?

Equal magnitude and opposite direction. Forces in a pair must be equal in size but opposite in direction.
A book rests on a table. Which force is the reaction to the table pushing up on the book?

The book pushing down on the table. Book's weight and table's support form the pair.
Identify the action–reaction pair when a car rear-ends another car.

Car A on car B; car B on car A. Both cars push on each other with equal force.
If object A pushes on object B with force $F$ , what is the force of B on A?

A force of $F$ in the opposite direction. Newton's third law: B pushes back with equal magnitude, opposite direction.
In a collision, which quantity can differ between the two objects even though forces are equal?

Acceleration. Equal forces on different masses produce different accelerations ( $a=F/m$ ).
Identify the actionreaction pair: a book rests on a table (contact forces only).

Book on table; table on book. The book pushes down on the table, and the table pushes up on the book.
What law states that forces in an interaction come in equal and opposite pairs?

Newton's third law of motion. States that every action has an equal and opposite reaction.
In a collision, if object A exerts force $F$ on object B, what force does B exert on A?

A force of magnitude $F$ in the opposite direction. Newton's Third Law requires equal magnitude but opposite direction.
Choose the correct pair: normal force on book by table pairs with what force?

Normal force on table by book. Book pushes down, table pushes up equally.
What is an action–reaction force pair in a collision between two objects?

Two forces on different objects, equal and opposite. Action-reaction pairs always involve two objects interacting.
Which option is the reaction force to "book pushes down on table"?

Table pushes up on book. The reaction acts on the book, completing the action-reaction pair.
In a collision, do action-reaction forces act on the same object or on different objects?

Different objects. Action-reaction pairs always act on two separate objects, never the same one.
Identify the actionreaction pair: a ball bounces off the floor during impact.

Ball on floor; floor on ball. During the bounce, ball and floor exert equal forces on each other.
Identify the action–reaction pair: a bowling ball collides with a pin.

Ball on pin; pin on ball. Ball strikes pin; pin pushes back on ball equally.
What is always true about the magnitudes of forces in an action-reaction pair?

They are equal in magnitude. Newton's third law requires equal force magnitudes.
Identify the reaction force to "bat pushes on ball" during a collision.

Ball pushes on bat. Newton's third law: the ball exerts an equal force back on the bat.
Identify the action–reaction pair: a soccer player kicks a ball; focus on contact forces only.

Foot on ball; ball on foot. The kick force and the ball's reaction force form the pair.
Identify the action-reaction pair when two ice skaters push off each other.

Skater A on B; skater B on A. Each skater pushes the other with equal force.
What is wrong with this claim: "A truck hits a car, so the truck's force is larger than the car's force"?

Action–reaction forces are equal in magnitude. Newton's third law: forces are always equal regardless of object mass.
What equation represents the magnitudes of an action–reaction pair forces?

$|F_{A\to B}|=|F_{B\to A}|$ . Magnitudes are equal regardless of object sizes.
Which statement is always true for an action–reaction pair: equal forces, equal accelerations, or equal masses?

Equal forces. Forces are always equal; accelerations depend on mass.
If object A exerts $12\,\text{N}$ on object B, what is the magnitude of B on A?

$12\,\text{N}$ . Newton's third law requires equal magnitude forces between objects.
What two features must an action–reaction force pair always have?

Equal magnitude and opposite direction. Action-reaction pairs are always equal in size but point in opposite directions.
Identify the action–reaction pair when a bat hits a ball: what force pairs with bat on ball?

Ball on bat. Ball exerts equal force back on bat during contact.
Which statement is always true for an action–reaction pair during a collision?

They act on different objects. Newton's third law requires the pair to act on separate objects.
Identify the action-reaction pair when a shopping cart collides with a wall.

Cart on wall; wall on cart. Wall exerts equal force back on cart during collision.
In a collision, if Object A exerts force $F$ on Object B, what force does B exert on A?

A force of magnitude $F$ in the opposite direction. Newton's third law: forces are always equal and opposite between objects.
If object A exerts $30\ \text{N}$ east on object B, what is B's force on A?

$30\ \text{N}$ west. Equal magnitude but opposite direction per Newton's third law.
Identify the action-reaction pair when a skateboarder pushes backward on the pavement.

Skateboarder on pavement; pavement on skateboarder. Skateboarder pushes pavement backward, pavement pushes skateboarder forward.
Which option correctly describes an actionreaction pair: same object or different objects?

Different objects. Action-reaction forces always act on separate objects, not the same one.
Identify the action-reaction pair when a bowling ball hits a pin.

Ball on pin; pin on ball. Ball pushes pin forward; pin pushes ball backward with equal force.
In a foot–soccer ball kick, identify the reaction force to "foot pushes on ball."

Ball pushes on foot. The ball exerts an equal force back on the foot.
On which objects do the two forces in an action-reaction pair act?

They act on different objects. One force acts on each object in the pair.
Which option is the reaction to "truck pushes on car" in a collision: A) road on truck B) car pushes on truck?

B) car pushes on truck. The reaction to truck-on-car must be car-on-truck (same interaction).
Identify the action-reaction pair when a car collides with a wall.

Car on wall; wall on car. The car pushes the wall, and the wall pushes back with equal force.
Which option identifies an action-reaction pair: A) forces on one object B) forces on two objects?

B) forces on two objects. Action-reaction pairs must act on two different objects, not the same object.
Which option correctly describes an action-reaction pair in a collision: same type of force or different types?

Same type of force (one interaction force pair). Both forces are contact forces from the same interaction.
Identify the action-reaction pair when a person jumps and pushes on the ground.

Person on ground; ground on person. Person pushes down on ground, ground pushes up on person with equal force.
Identify the reaction force to "skater A pushes on skater B" when they collide.

Skater B pushes on skater A. Each skater experiences an equal force from the other during collision.
Identify the action–reaction pair: a hammer strikes a nail.

Hammer on nail; nail on hammer. Hammer pushes nail down; nail pushes hammer up with equal force.
What two features must an action-reaction force pair always have?

Equal magnitude and opposite direction; act on different objects. Forces must be equal in size, opposite in direction, and act on separate objects.
Identify the action–reaction pair when a car rear-ends another car.

Rear car on front car; front car on rear car. In collision, each car pushes the other with equal but opposite forces.
What two features must an action-reaction force pair always have?

Equal magnitude and opposite direction. Action-reaction pairs must be equal in size but point in opposite directions.
A bowling ball hits a pin. Identify the action–reaction pair involving the ball and the pin.

Ball on pin; pin on ball. Each object exerts equal force on the other.
What is the action-reaction pair when a book rests on a table (normal force interaction)?

Table on book; book on table. Normal forces form action-reaction pairs at contact.
Identify the action-reaction pair when a hammer strikes a nail.

Hammer on nail; nail on hammer. Nail exerts equal force back on hammer during impact.
What two features must an actionreaction force pair always have?

Equal magnitude and opposite direction. Action-reaction pairs are always equal in size but opposite in direction.
Identify the action-reaction pair when a hockey puck hits the boards.

Puck on boards; boards on puck. Puck hits boards with force; boards hit puck back with equal force.
In a collision, if object A exerts a force of $50\,\text{N}$ on object B, what force does B exert on A?

$50\,\text{N}$ in the opposite direction. Newton's third law requires equal magnitude, opposite direction.
What equation represents the directions of an action–reaction pair forces as vectors?

$\vec{F}_{A\to B}=-\vec{F}_{B\to A}$ . Negative sign shows forces point in opposite directions.
Identify the reaction force to "bowling ball pushes on pin" during impact.

Pin pushes on bowling ball. The pin exerts an equal force back on the ball during impact.
Identify the action–reaction pair when a hammer hits a nail.

Hammer on nail; nail on hammer. Hammer pushes nail down; nail pushes hammer up with equal force.
Identify the action-reaction pair when a person jumps and pushes down on the ground.

Person on ground; ground on person. Ground pushes up on person as reaction to downward push.
If $F_{A\to B}=+20\,\text{N}$ (to the right), what is $F_{B\to A}$ ?

$-20\,\text{N}$ (to the left). Newton's third law: equal magnitude, opposite direction.
A heavy truck and a small car collide. Which experiences the larger force during contact?

Neither; the forces are equal in magnitude. Newton's third law applies regardless of mass - forces are always equal.
Identify the action-reaction pair when a foot kicks a soccer ball.

Foot on ball; ball on foot. When foot applies force to ball, ball applies equal force back to foot.
Identify the actionreaction pair: two ice skaters push off each other.

Skater A on B; skater B on A. Each skater pushes the other with equal and opposite forces.
A $2\,\text{kg}$ cart hits a $6\,\text{kg}$ cart. Which cart feels the larger force during contact?

Neither; both feel equal-magnitude forces. Newton's third law: forces are always equal regardless of mass.
What is wrong with calling weight and normal force an actionreaction pair on a book?

They act on the same object. Action-reaction pairs must act on different objects, not the same one.
Which statement is correct: action-reaction forces cancel each other on one object, or act on different objects?

They act on different objects (so they do not cancel on one object). Forces don't cancel because they're on separate objects.
Identify the action-reaction pair when a soccer player kicks a ball.

Foot on ball; ball on foot. The ball pushes back on the foot with equal force.
Identify the action-reaction pair when two ice skaters push off each other.

Skater A on skater B; skater B on skater A. Each skater pushes the other with equal force in opposite directions.
Which statement is correct: action–reaction forces cancel each other on one object?

No; they act on different objects, so they do not cancel on one object. Forces in a pair act on separate objects, so they can't cancel.
Identify the reaction force to "car pushes on barrier" in a crash.

Barrier pushes on car. The barrier exerts an equal and opposite force on the car.
During a collision, which object experiences the "action" force and which experiences the "reaction" force?

Each object experiences one of the pair. Neither is "first" - both forces occur simultaneously.
Identify the action-reaction pair: a foot kicks a soccer ball.

Foot on ball; ball on foot. The ball pushes back on the foot with equal force.
Identify the action–reaction pair when a soccer player kicks a ball.

Foot on ball; ball on foot. Foot applies force to ball; ball applies equal force back to foot.
Which interaction produces an action–reaction pair: contact forces, noncontact forces, or both?

Both contact and noncontact interactions. Newton's third law applies to all forces, whether objects touch or not.
Identify the action-reaction pair when a bat hits a baseball.

Bat on ball; ball on bat. Each object exerts a force on the other during contact.
Identify the action-reaction pair: a bat hits a baseball.

Bat on ball; ball on bat. Each object exerts an equal force on the other during contact.
What law states that forces between two interacting objects are equal in magnitude and opposite in direction?

Newton's Third Law. States that every action has an equal and opposite reaction.
Identify the action-reaction pair when a bat hits a baseball.

Bat on ball; ball on bat. The bat exerts force on ball, and ball exerts equal force back on bat.
Identify the action–reaction pair: two ice skaters push off each other.

Skater A on B; skater B on A. Each skater pushes the other; forces are equal and opposite.
Identify the action–reaction pair in a head-on collision between car $A$ and car $B$ .

Car $A$ on car $B$ ; car $B$ on car $A$ . Each car exerts an equal and opposite force on the other.
Identify the action–reaction pair in a collision between a hammer and a nail.

Hammer on nail; nail on hammer. Each object exerts a force on the other, forming the action-reaction pair.
If object $A$ exerts $50\,\text{N}$ on object $B$ , what is the magnitude of the force $B$ exerts on $A$ ?

$50\,\text{N}$ . Action-reaction forces are always equal in magnitude.
What is the correct statement of an action-reaction pair using symbols $F_{A\to B}$ and $F_{B\to A}$ ?

$F_{A\to B}=-F_{B\to A}$ . Negative sign shows opposite directions; magnitudes are equal.
Identify the action–reaction pair when a bat hits a baseball.

Bat on ball; ball on bat. Each object exerts a force on the other during contact.
Identify the action-reaction pair when a hammer strikes a nail.

Hammer on nail; nail on hammer. Hammer pushes nail down; nail pushes hammer up with equal force.
Identify whether this is an action-reaction pair: "wall on ball" and "floor on ball."

No; both forces act on the same object. Not a pair because both forces act on the ball, not different objects.
Identify the action-reaction pair when a car rear-ends a truck.

Car on truck; truck on car. Both vehicles exert equal forces on each other during the collision.
What is wrong with the claim "action and reaction forces cancel because they are equal and opposite"?

They do not cancel because they act on different objects. Forces can't cancel when they act on separate objects.
What is the reaction force to "Object A pushes on Object B" during a collision?

Object B pushes on Object A. Newton's third law: forces always come in pairs with swapped objects.
What is the key rule about which objects experience the forces in an actionreaction pair?

They act on two different objects. Each force in the pair acts on a different object, never the same one.
Choose the statement that is always true for an actionreaction pair: same object or different objects?

Different objects. Action-reaction pairs must involve two different objects interacting.
Which statement is correct in a collision: action–reaction forces cancel each other on one object, or they act on different objects?

They act on different objects, so they do not cancel on one object. Can't cancel because each acts on a separate object.
What two features must an action-reaction pair always have in a collision?

Equal magnitude and opposite direction. Action-reaction pairs always have the same strength but point in opposite directions.
Identify the action–reaction pair when a swimmer pushes water backward.

Swimmer on water; water on swimmer. Swimmer pushes water back; water pushes swimmer forward equally.
Identify whether "Earth pulls apple" and "ground pushes apple" form an action-reaction pair.

No; they are different interactions on the apple. Different force types (gravity vs. normal) acting on same object.
Which option is an action–reaction pair? A) tire-road B) weight-normal C) friction-normal

A) tire pushes road; road pushes tire. Only A shows forces between two objects; B and C act on the same object.
Identify the reaction force: A bowling ball hits a pin and pushes it forward.

The pin pushes backward on the bowling ball. The pin exerts an equal and opposite force back on the ball.
Which force is the reaction to "truck pushes on the car" in a collision?

Car pushes on the truck. The car must push back with equal force.
If object A exerts $10\ \text{N}$ east on object B, what force does B exert on A?

$10\ \text{N}$ west on A. Equal magnitude, opposite direction per Newton's third law.
Identify the action-reaction pair for gravitational attraction between Earth and the Moon.

Earth pulls Moon; Moon pulls Earth. Gravitational forces between objects are always equal and opposite pairs.
Identify the reaction force: A car pushes on a truck in a collision.

The truck pushes on the car. By Newton's third law, the truck pushes back with equal force.
If a bug hits a windshield, which object experiences the larger force during the collision?

Neither; the forces are equal in magnitude. Forces are equal; bug feels same force as windshield.
Identify the action-reaction pair when a rocket expels gas downward.

Rocket on gas; gas on rocket. Gas pushes rocket up as reaction to being expelled down.
Identify the action–reaction pair: a hammer strikes a nail; focus on contact forces only.

Hammer on nail; nail on hammer. Each object pushes the other with equal force during impact.
In a collision, if object A pushes object B to the right, what direction is the force on A from B?

To the left. Action-reaction forces are always in opposite directions.
What law states that forces in an interaction come in equal and opposite pairs?

Newton's third law. States that for every action force, there's an equal and opposite reaction force.
Identify the reaction force: "the ground pushes up on the falling ball during impact."

The ball pushes down on the ground. Ground and ball exchange equal and opposite forces on impact.
What is the most important rule for identifying an action–reaction pair in a collision?

The forces act on two different objects. Action-reaction pairs never act on the same object.
Identify the actionreaction pair: a car rear-ends another car.

Car 1 on car 2; car 2 on car 1. In the collision, each car exerts equal force on the other.
Identify the action–reaction pair: a car collides with a wall.

Car on wall; wall on car. Car pushes wall; wall pushes back on car with equal force.
A light cart and a heavy cart collide. Which cart has the larger acceleration magnitude during impact?

The lighter cart. Same force but lighter mass gives larger acceleration by $F=ma$ .
Identify the action–reaction pair when a hammer strikes a nail.

Hammer on nail; nail on hammer. The nail pushes back on the hammer during impact.
Are action–reaction forces ever acting on the same object at the same time?

No, they act on different objects. Each force acts on a different object in the interaction.
Identify the action–reaction pair: a bowling ball hits a pin; focus on contact forces only.

Ball on pin; pin on ball. Impact forces between objects are always equal and opposite.
A truck hits a cone. Which object experiences the larger contact force during the collision?

Neither; forces are equal in magnitude. Newton's third law applies regardless of object sizes or masses.
What law states that forces between two interacting objects are equal in magnitude and opposite in direction?

Newton's third law. States that for every action, there is an equal and opposite reaction.
What is always true about the sizes of the forces in an action–reaction pair, even if masses differ?

The magnitudes are equal. Newton's third law applies regardless of object masses.
Identify the key rule about where action–reaction forces act (same object or different objects).

They act on different objects. Action-reaction pairs never act on the same object, always on two different objects.
Identify the action–reaction pair when a book rests on a table (contact forces).

Book on table; table on book. Book pushes down on table; table pushes up on book (normal force).
Identify the action–reaction pair when a bowling ball hits pins: what force pairs with ball on pins?

Pins on ball. Pins push back on ball with equal total force.
What law states that forces between two interacting objects come in equal and opposite pairs?

Newton's third law of motion. States that forces always come in equal and opposite pairs.
Which force is the reaction to "wall pushes on your hand" when you press a wall?

Your hand pushes on the wall. Newton's third law: wall pushes hand, so hand must push wall equally.
Identify the action-reaction pair when a bat hits a ball.

Bat on ball; ball on bat. The bat exerts force on ball, and ball exerts equal force back on bat.
Identify the action-reaction pair: a hammer strikes a nail.

Hammer on nail; nail on hammer. Both objects push on each other with equal force during impact.
A rocket pushes exhaust gases backward. Which force is the reaction to rocket on gases?

Gases on rocket. Exhaust pushes rocket forward with equal force.
Which option describes an action-reaction pair: A) same object B) different objects?

B) Different objects. Action-reaction pairs must act on different objects, not the same one.
What is the most important rule for identifying an actionreaction pair in a collision?

They act on two different objects. Action-reaction pairs never act on the same object, always on different objects.
Which forces form an action–reaction pair: "Earth pulls on apple" and which other force?

Apple pulls on Earth. Gravity works both ways with equal force.
What two features must an action–reaction force pair always have?

Equal magnitude and opposite direction. Action-reaction pairs must be equal in size but opposite in direction.
Identify the action–reaction pair when a rocket pushes exhaust gases backward.

Rocket on gases; gases on rocket. Rocket pushes gases down; gases push rocket up with equal force.
A truck hits a small car. Which statement is correct about the forces during the collision?

Each exerts equal-magnitude force on the other. Newton's third law applies regardless of object size or mass.
Which force is the reaction to "the wall pushes on the ball" during a bounce?

The ball pushes on the wall. Newton's third law: wall on ball, ball on wall.
Identify the action–reaction pair: a soccer ball hits a player's head.

Ball on head; head on ball. Ball pushes head; head pushes ball with equal force.
Identify the action-reaction pair: a car rear-ends a truck.

Car on truck; truck on car. Both vehicles push on each other during collision.
Identify the action–reaction pair when a bowling ball strikes a pin.

Ball on pin; pin on ball. During impact, ball pushes pin while pin pushes back on ball equally.
Identify the action-reaction pair when a hammer strikes a nail.

Hammer on nail; nail on hammer. The hammer pushes nail down, and nail pushes hammer up with equal force.
Identify the action-reaction pair when a swimmer pushes water backward.

Swimmer on water; water on swimmer. Water pushes swimmer forward as reaction to being pushed.
Choose the correct reason accelerations can differ in a collision: same force but different ____.

Mass. Different masses experiencing equal forces have different accelerations.
Which pair is NOT an action–reaction pair: "Earth pulls on ball" paired with which force?

Normal force of ground on ball (not the third-law partner). Normal and gravitational forces act on same object, not a third-law pair.
Identify the action-reaction pair when a hammer strikes a nail.

Hammer on nail; nail on hammer. Hammer pushes nail forward; nail pushes hammer backward with equal force.
Which statement is always true about the sizes of forces in an action–reaction pair?

They have equal magnitude. Newton's third law states forces in a pair are always equal.
Which force is the reaction to "tires push backward on the road" as a car accelerates?

Road pushes forward on the tires. By Newton's third law, road must push forward when tires push backward.
Identify the reaction force: "the wall pushes on the person" during a collision with a wall.

The person pushes on the wall. Action-reaction pairs involve mutual forces between objects.
Identify the action–reaction pair: a bat hits a baseball; focus on contact forces only.

Bat on ball; ball on bat. Each object exerts an equal force on the other during contact.
What is the reaction force to "Earth pulls on the falling ball (gravity)"?

Ball pulls on Earth (gravity). Gravity is mutual: Earth pulls ball down, ball pulls Earth up equally.
Identify the key check to avoid confusion: Do action and reaction forces act on the same object?

No, they act on different objects. Key distinction: each force acts on a different object.
In a collision, which statement is correct about forces: equal or one larger?

The forces are equal in magnitude. Newton's third law requires action-reaction forces to have equal magnitudes.

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