Action Reaction Forces - Middle School Physical Science
Card 1 of 25
Identify the action–reaction pair: a bowling ball hits a pin; focus on contact forces only.
Identify the action–reaction pair: a bowling ball hits a pin; focus on contact forces only.
Tap to reveal answer
Ball on pin; pin on ball. Impact forces between objects are always equal and opposite.
Ball on pin; pin on ball. Impact forces between objects are always equal and opposite.
← Didn't Know|Knew It →
Identify the action–reaction pair: a soccer player kicks a ball; focus on contact forces only.
Identify the action–reaction pair: a soccer player kicks a ball; focus on contact forces only.
Tap to reveal answer
Foot on ball; ball on foot. The kick force and the ball's reaction force form the pair.
Foot on ball; ball on foot. The kick force and the ball's reaction force form the pair.
← Didn't Know|Knew It →
Which statement is correct: action–reaction forces cancel each other on one object?
Which statement is correct: action–reaction forces cancel each other on one object?
Tap to reveal answer
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.
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.
← Didn't Know|Knew It →
Which statement is always true about the directions of forces in an action–reaction pair?
Which statement is always true about the directions of forces in an action–reaction pair?
Tap to reveal answer
They are opposite directions. Newton's third law requires paired forces to point in opposite directions.
They are opposite directions. Newton's third law requires paired forces to point in opposite directions.
← Didn't Know|Knew It →
Which statement is always true about the sizes of forces in an action–reaction pair?
Which statement is always true about the sizes of forces in an action–reaction pair?
Tap to reveal answer
They have equal magnitude. Newton's third law states forces in a pair are always equal.
They have equal magnitude. Newton's third law states forces in a pair are always equal.
← Didn't Know|Knew It →
Which statement is always true for an action–reaction pair during a collision?
Which statement is always true for an action–reaction pair during a collision?
Tap to reveal answer
They act on different objects. Newton's third law requires the pair to act on separate objects.
They act on different objects. Newton's third law requires the pair to act on separate objects.
← Didn't Know|Knew It →
What is an action–reaction force pair in a collision between two objects?
What is an action–reaction force pair in a collision between two objects?
Tap to reveal answer
Two forces on different objects, equal and opposite. Each object exerts a force on the other during contact.
Two forces on different objects, equal and opposite. Each object exerts a force on the other during contact.
← Didn't Know|Knew It →
What law states that forces between two interacting objects are equal in magnitude and opposite in direction?
What law states that forces between two interacting objects are equal in magnitude and opposite in direction?
Tap to reveal answer
Newton’s third law. States that for every action, there is an equal and opposite reaction.
Newton’s third law. States that for every action, there is an equal and opposite reaction.
← Didn't Know|Knew It →
Which option is the reaction force to “book pushes down on table”?
Which option is the reaction force to “book pushes down on table”?
Tap to reveal answer
Table pushes up on book. The reaction acts on the book, completing the action-reaction pair.
Table pushes up on book. The reaction acts on the book, completing the action-reaction pair.
← Didn't Know|Knew It →
Which option is the reaction force to “wall pushes on your hand” when you punch a wall?
Which option is the reaction force to “wall pushes on your hand” when you punch a wall?
Tap to reveal answer
Your hand pushes on wall. The reaction acts on the wall, completing the force pair.
Your hand pushes on wall. The reaction acts on the wall, completing the force pair.
← Didn't Know|Knew It →
Identify the reaction force to “Earth pulls on an apple (gravity)” while it falls.
Identify the reaction force to “Earth pulls on an apple (gravity)” while it falls.
Tap to reveal answer
Apple pulls on Earth (gravity). Gravitational forces between objects are mutual and equal.
Apple pulls on Earth (gravity). Gravitational forces between objects are mutual and equal.
← Didn't Know|Knew It →
Which pair is NOT an action–reaction pair: “Earth pulls on ball” paired with which force?
Which pair is NOT an action–reaction pair: “Earth pulls on ball” paired with which force?
Tap to reveal answer
Normal force of ground on ball (not the third-law partner). Normal and gravitational forces act on same object, not a third-law pair.
Normal force of ground on ball (not the third-law partner). Normal and gravitational forces act on same object, not a third-law pair.
← Didn't Know|Knew It →
Which pair is an action–reaction pair: “friction on box by floor” and which matching force?
Which pair is an action–reaction pair: “friction on box by floor” and which matching force?
Tap to reveal answer
Friction on floor by box. Friction forces between surfaces form action-reaction pairs.
Friction on floor by box. Friction forces between surfaces form action-reaction pairs.
← Didn't Know|Knew It →
A light cart and a heavy cart collide. Which cart has the larger acceleration magnitude during impact?
A light cart and a heavy cart collide. Which cart has the larger acceleration magnitude during impact?
Tap to reveal answer
The lighter cart. Same force but lighter mass gives larger acceleration by $F=ma$.
The lighter cart. Same force but lighter mass gives larger acceleration by $F=ma$.
← Didn't Know|Knew It →
A truck hits a cone. Which object experiences the larger contact force during the collision?
A truck hits a cone. Which object experiences the larger contact force during the collision?
Tap to reveal answer
Neither; forces are equal in magnitude. Newton's third law applies regardless of object sizes or masses.
Neither; forces are equal in magnitude. Newton's third law applies regardless of object sizes or masses.
← Didn't Know|Knew It →
In a collision, if object A exerts a force of $50,\text{N}$ on object B, what force does B exert on A?
In a collision, if object A exerts a force of $50,\text{N}$ on object B, what force does B exert on A?
Tap to reveal answer
$50,\text{N}$ in the opposite direction. Newton's third law requires equal magnitude, opposite direction.
$50,\text{N}$ in the opposite direction. Newton's third law requires equal magnitude, opposite direction.
← Didn't Know|Knew It →
Identify the action–reaction pair: a bat hits a baseball; focus on contact forces only.
Identify the action–reaction pair: a bat hits a baseball; focus on contact forces only.
Tap to reveal answer
Bat on ball; ball on bat. Each object exerts an equal force on the other during contact.
Bat on ball; ball on bat. Each object exerts an equal force on the other during contact.
← Didn't Know|Knew It →
Identify the action–reaction pair: a hammer strikes a nail.
Identify the action–reaction pair: a hammer strikes a nail.
Tap to reveal answer
Hammer on nail; nail on hammer. Hammer pushes nail down; nail pushes hammer up with equal force.
Hammer on nail; nail on hammer. Hammer pushes nail down; nail pushes hammer up with equal force.
← Didn't Know|Knew It →
Identify the action–reaction pair: a car collides with a wall.
Identify the action–reaction pair: a car collides with a wall.
Tap to reveal answer
Car on wall; wall on car. Car pushes wall; wall pushes back on car with equal force.
Car on wall; wall on car. Car pushes wall; wall pushes back on car with equal force.
← Didn't Know|Knew It →
Identify the action–reaction pair: two ice skaters push off each other.
Identify the action–reaction pair: two ice skaters push off each other.
Tap to reveal answer
Skater A on B; skater B on A. Each skater pushes the other; forces are equal and opposite.
Skater A on B; skater B on A. Each skater pushes the other; forces are equal and opposite.
← Didn't Know|Knew It →
Which option is an action–reaction pair: (A) friction and normal on one box, (B) box on floor and floor on box?
Which option is an action–reaction pair: (A) friction and normal on one box, (B) box on floor and floor on box?
Tap to reveal answer
Option B. Option A has both forces on one object; B shows forces on different objects.
Option B. Option A has both forces on one object; B shows forces on different objects.
← Didn't Know|Knew It →
Identify the action–reaction pair: a bowling ball collides with a pin.
Identify the action–reaction pair: a bowling ball collides with a pin.
Tap to reveal answer
Ball on pin; pin on ball. Ball strikes pin; pin pushes back on ball equally.
Ball on pin; pin on ball. Ball strikes pin; pin pushes back on ball equally.
← Didn't Know|Knew It →
What does the equality in Newton’s third law mean for an interaction: $F_{A\rightarrow B}$ and $F_{B\rightarrow A}$?
What does the equality in Newton’s third law mean for an interaction: $F_{A\rightarrow B}$ and $F_{B\rightarrow A}$?
Tap to reveal answer
$F_{A\rightarrow B} = -F_{B\rightarrow A}$. Forces are equal in magnitude but opposite in direction (negative sign).
$F_{A\rightarrow B} = -F_{B\rightarrow A}$. Forces are equal in magnitude but opposite in direction (negative sign).
← Didn't Know|Knew It →
Identify the action–reaction pair: a soccer ball hits a player’s head.
Identify the action–reaction pair: a soccer ball hits a player’s head.
Tap to reveal answer
Ball on head; head on ball. Ball pushes head; head pushes ball with equal force.
Ball on head; head on ball. Ball pushes head; head pushes ball with equal force.
← Didn't Know|Knew It →
What is wrong with this claim: “A truck hits a car, so the truck’s force is larger than the car’s force”?
What is wrong with this claim: “A truck hits a car, so the truck’s force is larger than the car’s force”?
Tap to reveal answer
Action–reaction forces are equal in magnitude. Newton's third law: forces are always equal regardless of object mass.
Action–reaction forces are equal in magnitude. Newton's third law: forces are always equal regardless of object mass.
← Didn't Know|Knew It →