What is Newton's laws: Definition and 478 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. B

    How Does Static Friction Determine the Limits of Force on an Inclined Wedge?

    Homework Statement A block of mass.5kg rests on the inclined surface of a wedge of mass 2kg. The wedge is acted on by a horizontal force F and slides on a frictionless surface. (a) If the coefficient of static friction between the wedge and the block is .8 and the angle of incline is 35...
  2. I

    Force's and Newton's Laws of Motion

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  3. N

    Newton's Laws and an electron of mass

    1. An electron of mass 9.11 x 10^-31 kg has an initial speed of 4.00 x 10^5 m/s. It travels in a straight line, and its speed increases to 6.00 x 10^5 m/s in a distance of 3.00 cm. (a) Assuming its acceleration is constant, determine the force exerted on the electron. N (in the direction of...
  4. A

    Newton's Laws: Simple Constant Force Problem

    A car that weighs 12000.0 N is initially moving at a speed of 30.0 km/hr when the brakes are applied and the car is brought to a stop in 4.1 s. Find the magnitude of the force that stops the car, assuming it is constant. Figured this one out, got: v0 = 8.33 m/s, a = -2.03 m/s^2, F = 2.49 X 10^3...
  5. S

    Analytical Classical Dynamics: Newton's Laws

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  6. P

    Newton's laws problems HELP

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  7. S

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  8. A

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  9. B

    How Do You Calculate Initial Acceleration in Newton's Laws Problems?

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  10. L

    Work-Kinetic Energy Contrasting Newton's Laws?

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  11. J

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  12. P

    Newton's Laws of motion

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  13. E

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  14. P

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  15. I

    How Does Emptying Sand Affect a Balloon's Acceleration?

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  16. Q

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  17. E

    Applying Newton's Laws of Motion

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  18. I

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  19. G

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  20. S

    How Do Forces Determine the Movement of a Block on an Inclined Plane?

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  21. D

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  22. J

    :-$ Calculus Based Physics: Newton's Laws Problem

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  23. D

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  24. J

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  26. D

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  29. M

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  30. B

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  31. B

    How Does a Vertical Force Affect the Acceleration of a Two-Block System?

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  32. S

    Homework Question (Newton's Laws)

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  33. N

    Newton's Laws of Motion: Fundamental Law

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  34. A

    How Do Newton's Laws Apply to a Tug-of-War on Ice?

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  35. G

    Newton's Laws; ramps and pulleys

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  36. E

    How Do You Calculate Tension and Pole Force on a Leaning Tether Ball?

    Homework Statement A tether ball leans against the post to which it is attached. If the string to which the ball is attached is 1.80m long, the ball has a radius of .200m, and the ball has a mass of .500kg, what are the tension in the rope and the force the pole exerts on the ball? assume that...
  37. N

    Box on a Toboggan - Newton's Laws

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  38. S

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  39. S

    Angular motion using Newton's Laws

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  40. T

    Newton's Laws - Tetherball on a pole

    A tether ball leans against the post to which it is attached (Fig. 5-40). If the string to which the ball is attached is 2.00 m long, the ball has a radius of 0.300 m, and the ball has a mass of 0.400 kg, what are the tension in the rope and the force the pole exerts on the ball? Neglect any...
  41. R

    How Do You Calculate the Force of Air Friction on a Falling Basketball?

    NEWTON'S LAWS: please help! :eek: so I am kinda stuck. problem: a 2.5kg basketball is dropped from the top of a building. its acceleration is found to be 9.4m/s2 as it drops to the ground. What is the force of air friction on the ball as it falls? so like... a=9.4 m-2.5kg...
  42. S

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  43. J

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  44. A

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  45. B

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  46. Elkay

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  47. A

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  48. P

    Classical Physics from Newton's Laws?

    How much of classical physics can be purely derived from Newton's 3 Laws of motion? Can Newton's laws derive conservation of momentum? Or any other conservation laws? Consider this example Let there be no external forces. When standing in a stationary bus and the bus accelerates forwards...
  49. X

    Can Conservation Laws be Derived from Symmetry and Newton's Laws?

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  50. P

    Newton's Laws - Weight Lifting

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