Name: newton's first law and reference frames
Uploaded: 2023-04-30T10:54:21.000Z
Duration: 1 min 3 s
Channel: JoVE

K12 Standards

Pennsylvania State Academic Standards

9-12

Physical Science

Forces and Interactions

3.2.9-12.J

Inertial Frames of Reference

El marco de referencia en el que las leyes de Newton son válidas se denomina marco de referencia inercial. El objeto relativo a este marco de referencia continúa permaneciendo en reposo o moviéndose con una velocidad constante.
Pensemos en un coche en movimiento. El pasajero se mueve junto con el automóvil en relación con la Tierra. Cuando el automóvil se detiene repentinamente, el pasajero experimenta un empuje hacia adelante a pesar de que ninguna fuerza neta actúe sobre él.
Aunque el pasajero se mueve hacia adelante en relación con el automóvil, su velocidad en relación con la Tierra se mantiene.
La inercia del pasajero tiende a mantener su velocidad con respecto a la Tierra debido a la primera ley del movimiento de Newton. Aquí, el marco de referencia unido a la Tierra puede considerarse como un marco de referencia inercial.
A pesar de que la velocidad de la Tierra no es constante debido a su rotación y revolución, se puede aproximar como un marco inercial, ya que sus efectos son insignificantes en el movimiento de los objetos en la superficie de la Tierra.

No se han declarado conflictos de interés.

marcos inerciales de referencia

La primera ley de Newton generalmente se considera una declaración sobre marcos de referencia. Proporciona un método para identificar un tipo especial de marco de referencia: el marco de referencia inercial. En principio, podemos hacer que la fuerza neta sobre un cuerpo sea cero. Si su velocidad relativa a un marco dado es constante, entonces se dice que ese marco es inercial. Por lo tanto, según la definición, un marco de referencia inercial es un marco de referencia donde se cumple la primera ley de Newton. La primera ley de Newton se aplica a objetos con velocidad constante. A partir de este hecho, podemos inferir lo siguiente: Un marco de referencia que se mueve con velocidad constante con respecto a un marco inercial también es inercial. ¿Son comunes los marcos inerciales en la naturaleza? Resulta que, dentro del margen de error experimental, un marco de referencia en reposo con respecto a las estrellas más distantes o "fijas" es inercial. Todos los marcos que se mueven uniformemente con respecto a este marco fijo de estrellas también son inerciales. Por ejemplo, un marco de referencia no rotante adjunto al Sol es, para todos los propósitos prácticos, inercial, porque su velocidad relativa a las estrellas fijas no varía en más de una parte en 1010. La Tierra acelera en relación con las estrellas fijas porque gira sobre su eje y gira alrededor del Sol; por lo tanto, un marco de referencia adjunto a su superficie no es inercial. Sin embargo, para la mayoría de los problemas, dicho marco sirve como una aproximación suficientemente precisa a un marco inercial porque la aceleración de un punto en la superficie de la Tierra en relación con las estrellas fijas es relativamente pequeña (< 3.4 × 10−2 m/s2). Por lo tanto, consideramos que los marcos de referencia fijos en la Tierra son inerciales a menos que se indique lo contrario. Finalmente, ningún marco inercial en particular es más especial que otro. En lo que respecta a las leyes de la naturaleza, todos los marcos inerciales son equivalentes. Al analizar un problema, elegimos un marco inercial sobre otro simplemente por conveniencia. Este texto está adaptado de <a href="https://openstax.org/books/university-physics-volume-1/pages/5-2-newtons-first-law">Openstax, University Physics Volume 1, Section 5.2: Newton's First Law.</a>

Marcos inerciales de referencia

La primera ley de Newton suele considerarse una afirmación sobre los marcos de referencia. Proporciona un método para identificar un tipo especial de referencia ...

Education

Educación

JoVE Core

Physics

Física

Unit 1

Unidad 1

Newton's Laws of Motion

Leyes del movimiento de Newton

KEY TERMS AND CONCEPTS

TÉRMINOS Y CONCEPTOS CLAVE

newton's first law and reference frames

Newton's first law helps identify inertial reference frames. An inertial reference frame is one in which Newton's first law holds true. In that frame, an object with no net force moves at constant velocity.

A key idea is that any frame moving at constant velocity relative to an inertial frame is also inertial. For that reason, inertial frames can be found by comparing motion from one frame to another. The laws of physics do not give one inertial frame special status over another.

In nature, a frame at rest relative to the most distant fixed stars is inertial within experimental error. Any frame moving uniformly with respect to that fixed-star frame is also inertial. A non-rotating frame attached to the Sun is, for practical purposes, inertial because its velocity relative to the fixed stars changes by less than one part in 10^10.

A frame attached to Earth's surface is not truly inertial because Earth rotates on its axis and revolves around the Sun. Even so, the acceleration of a point on Earth's surface relative to the fixed stars is small, less than 3.4 x 10^-2 m/s^2. That is why Earth-fixed frames are usually treated as inertial unless stated otherwise.

Newton's First Law and Reference Frames

force

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types of forces

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newton's first law: introduction

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Newton's first law of motion explains inertia and how forces change motion. Motion can be striking to observe, from a dolphin jumping from water to a bird in flight or a satellite moving in orbit. The study of motion is kinematics, which describes velocity and acceleration. Dynamics goes further by examining the forces that affect moving objects and systems. Newton's laws of motion are the foundation of dynamics. They are simple in form, but they describe a wide range of natural behavior.

newton's first law: application

Newton's First Law and Friction

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newton's second law

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newton's third law: introduction

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key terms and concepts

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Newton's First Law and Reference Frames | JoVE K12

physics

JoVE Core Física presenta la teoría y la aplicación de conceptos físicos fundamentales, como la cinemática, dinámica, mecánica de fluidos, estática, ondas y acústica, mediante animaciones audiovisuales concisas y fáciles de entender. Además, los vídeos de científicos en acción muestran la aplicación de los conceptos relacionados en experimentos de investigación clásicos y originales, realizados en laboratorios de todo el mundo.

Louisiana Student Standards for Science

High School

motion-and-stability-forces-and-interactions

Motion And Stability: Forces And Interactions

HS-PS2-2

HS-PS2-3

ohios-learning-standards-and-model-curriculum

Ohio’s Learning Standards and Model Curriculum

Forces And Motion

Motion

Tennessee Academic Standards

Motion and Stability: Forces and Interactions

PHYS.PS2.14

Virginia  Standards of Learning

HIgh School

PS.8

PS.8.b

PH.3

PH.3.a

Next Generation Science Standards

Florida Department of Education

SC.912.P.12

SC.912.P.12.3

SC.912.P.12.8

SC.912.P.12.9

Texas Essential Knowledge and Skills

PHYS.5

PHYS.5.C

new-york-state-science-learning-standards

New York State Science Learning Standards

HS. Forces and Interactions

HS-PS2-1.

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3.2.9-12.I

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3.2.9-12.K

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3.2.9-12.L

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3.2.9-12.M

Newton's First Law and Reference Frames

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