Newton's Third Law

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Force Noun

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[forss]

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Force

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An interaction, such as a push or a pull, that when applied to an object can cause a change in its motion.

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Example: A person pushing on a wall creates an 'action' force; the wall pushes back on the person with an equal and opposite 'reaction' force.

Front

Action-Reaction Forces Noun

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[ak-shun ree-ak-shun for-sez]

Back

Action-Reaction Forces

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A pair of interacting forces that are equal in magnitude and opposite in direction, with each force acting on a different object.

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Example: The Earth pulls on another celestial body with a force (action), and the body pulls back on Earth with an equal and opposite force (reaction).

Front

Action Force Noun

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[ak-shun forss]

Back

Action Force

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In a force pair, the initial force exerted by a first object onto a second object.

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Example: The force from the explosion pushes the cannon backward (action force), while an equal and opposite force pushes the cannonball forward (reaction force).

Front

Reaction Force Noun

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[ree-ak-shun forss]

Back

Reaction Force

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The force exerted by a second object back onto the first, which is equal in strength and opposite in direction to the action force.

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Example: The book's weight pushes down on the table (action), and the table pushes up on the book with an equal and opposite force (reaction).

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Magnitude Noun

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[mag-ni-tood]

Back

Magnitude

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The size, amount, or strength of a force, often represented by the length of an arrow in a force diagram.

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Example: This diagram shows a vector, which represents a force. The length of the arrow, labeled 'Magnitude,' illustrates the size or strength of the force.

Front

Balanced Forces Noun

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[bal-ansd for-sez]

Back

Balanced Forces

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Equal and opposite forces that act on the same object, which cancel each other out and do not change the object's motion.

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Example: Two people pull a rope with equal and opposite force, so the rope does not move, demonstrating balanced forces.

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Normal Force Noun

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[nor-muhl forss]

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Normal Force

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A contact support force exerted by a surface on an object resting on it, which acts perpendicular to the surface.

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Example: An object on a surface experiences an upward normal force from the surface, while the surface experiences an equal and opposite downward normal force from the object.

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Gravitational Force Noun

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[grav-i-tey-shun-ul forss]

Back

Gravitational Force

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A fundamental non-contact force of attraction that exists between any two objects that have mass.

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Example: The Earth pulls on the Moon with a gravitational force (F1), and the Moon pulls back on the Earth with an equal and opposite force (F2).

Front

Non-contact Force Noun

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[non-kon-takt forss]

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Non-contact Force

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A force applied to an object by another body that is not in direct physical contact with it.

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Example: The magnetic force between two magnets is a non-contact force; they attract each other without touching, demonstrating an equal and opposite action-reaction force pair.