What is Newton's first law: Definition and 68 Discussions

In classical mechanics, Newton's laws of motion are three laws that describe the relationship between the motion of an object and the forces acting on it. The first law states that an object either remains at rest or continues to move at a constant velocity, unless it is acted upon by an external force. The second law states that the rate of change of momentum of an object is directly proportional to the force applied, or, for an object with constant mass, that the net force on an object is equal to the mass of that object multiplied by the acceleration. The third law states that when one object exerts a force on a second object, that second object exerts a force that is equal in magnitude and opposite in direction on the first object.
The three laws of motion were first compiled by Isaac Newton in his Philosophiæ Naturalis Principia Mathematica (Mathematical Principles of Natural Philosophy), first published in 1687. Newton used them to explain and investigate the motion of many physical objects and systems, which laid the foundation for Newtonian mechanics.

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  1. A

    Newton's First Law & Constant Velocity Car

    Homework Statement What can be said about a car traveling at constant velocity on a street, keeping in mind Newton's first law? Homework Equations The Attempt at a Solution My first reaction to this question is "But a car is not a particle." Assuming the car is a particle, then it...
  2. A

    Understanding Newton's First Law for Force Tables

    I did an experiment on a force table with pulleys and weights. We were suppose to, through trial and error, find weights and add them on strings that were placed at different angles, so that the ring in the middle would become centered. Attached is the data table. I am suppose to calculate the...
  3. M

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  4. B

    Newton's First Law straight line speed

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  5. A

    Newton's 1st Law: Motion & Astronauts

    Newton's first law states that a body in motion tends to stay in motion and that's why when you're driving a car and then suddenly stop you get pushed at the same speed you were traveling. the Earth orbits the sun at 64,000 miles and the Earth's rotation is 1000 miles per a hour. my question...
  6. L

    A traffic accident with Newton's first law

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  7. R

    Newton's 1st Law: Incl in 2nd Law? Reasons/Ex

    Is included in the second law? Give reasons with examples. :rolleyes:
  8. H

    What is the point of Newton's First Law?

    What is the point of Newton's First Law? The first law says that "The state of motion of an object will not change unless acted upon by an outside force". In layman's terms, this means that the object's velocity won't change unless there is a net force (at least that is how our physics teacher...
  9. ranger

    Question on Newton's first law of motion

    Okay, so its stated that a body in motion stays uniformly in motion unless influenced by an external force. But what happens if that force is internal? For example, a rock moving in space that explodes from the inside. This causes the rock to fragment and move in different directions. This has...
  10. E

    Newton's First Law and objects in motion

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  11. P

    Explaining Newton's First Law & the Dropped Weight Trolley

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  12. B

    Solving Newton's First Law: Spider Attached to Two Threads

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  13. G

    What Is Inertia and How Does It Influence Motion?

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  14. B

    Need help on difficult Newton's First Law Question

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  15. B

    How Does Doubling the Force Affect the Speed of an Arrow?

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  16. W

    Friction make observing Newton's first law of motion difficult?

    Why can friction make observing Newton's first law of motion difficult?
  17. W

    What is Newton's First Law of Motion and how does it explain objects at rest?

    Hey, Could anyone give me good examples of Newton's First Law of Motion? THANKS ALOT, Michael
  18. H

    Newton's First Law of Motion & Skidding on Icy Roads

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