Name: tracking motion with position and displacement
Uploaded: 2023-09-22T11:49:39.000Z
Duration: 1 min 31 s
Channel: JoVE

Para describir el movimiento de un objeto, su posición debe especificarse en relación con un marco de referencia conveniente. Un conjunto arbitrario de ejes que describe la posición y el movimiento de un objeto se conoce como marco de referencia.
Generalmente, la Tierra o los objetos estacionarios en la Tierra se utilizan como marcos de referencia. Por ejemplo, la posición de un avión durante su despegue podría describirse con respecto a la Tierra en su conjunto o a la torre de control del aeropuerto. Para describir la posición de un objeto a lo largo de un movimiento unidimensional, a menudo usamos la variable x.
Ahora, supongamos que un objeto se mueve en relación con un marco de referencia, por ejemplo, un automóvil se mueve hacia la izquierda en relación con un edificio, luego la posición del automóvil cambia. Este cambio de posición se denomina desplazamiento.
Sin embargo, el valor numérico de x a lo largo de una línea recta define la posición de un objeto donde podría estar ubicado. Cualquier cambio de posición a lo largo de esta línea se indica mediante el desplazamiento, donde Δx es el desplazamiento y se calcula restando la posición inicial de la posición final. Es una cantidad vectorial ya que indica la dirección y, dependiendo de la elección de la dirección positiva, puede ser positiva o negativa.

posición y desplazamiento

La posición de un objeto define su ubicación con relación a un marco de referencia conveniente en cualquier momento particular. Un marco de referencia es un conjunto arbitrario de ejes desde los cuales se describen la posición y el movimiento de un objeto. La Tierra se utiliza a menudo como un marco de referencia y, a menudo, describimos la posición de un objeto con relación a los objetos estacionarios en la Tierra. Por ejemplo, el lanzamiento de un cohete podría describirse en términos de la posición del cohete con respecto a la Tierra en su conjunto. Por otro lado, la posición de un ciclista podría describirse en términos de dónde está con relación a los edificios que pasa. En otros casos, utilizamos marcos de referencia que no son estacionarios, sino que están en movimiento con respecto a la Tierra. Para describir la posición de una persona en un avión, por ejemplo, utilizamos el avión, no la Tierra, como marco de referencia. Para describir la posición de un objeto que experimenta un movimiento unidimensional, a menudo utilizamos la variable x. 

 Si un objeto se mueve con relación a un marco de referencia, entonces la posición del objeto cambia. Por ejemplo, si un profesor se mueve hacia la derecha con relación a una pizarra, entonces la posición del profesor ha cambiado. Este cambio en posición se llama desplazamiento. La palabra desplazamiento implica que un objeto se ha movido o ha sido desplazado. Aunque la posición es el valor numérico de x a lo largo de una línea recta donde un objeto podría estar ubicado, el desplazamiento indica el cambio en posición a lo largo de esta línea. Dado que el desplazamiento indica dirección, el desplazamiento es una cantidad vectorial y puede ser positivo o negativo, dependiendo de qué dirección se elija como positiva. 

 Además, un análisis del movimiento puede contener varios desplazamientos en él. Por ejemplo, si la derecha es positiva, y un objeto se mueve 2 m hacia la derecha, luego 4 m hacia la izquierda, los desplazamientos individuales son de 2 m y -4 m, respectivamente. El desplazamiento se denota como Δx, que es el cambio en posición. Siempre resolvemos el desplazamiento restando la posición inicial de la posición final. 

 Este texto está adaptado de <a href="https://openstax.org/books/university-physics-volume-1/pages/3-1-position-displacement-and-average-velocity">Openstax, University Physics Volume 1, Section 3.1: Position, Displacement and Average Velocity</a>.

Posición y desplazamiento

La posición de un objeto define su ubicación en relación con un marco de referencia conveniente en un momento determinado. Un marco de referencia es un sistema arbitrario ...

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Unit 1

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Physics Basics

Conceptos básicos de física

KEY TERMS AND CONCEPTS

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Position and Displacement

tracking motion with position and displacement

Position and displacement are key ideas in straight-line motion. Position tells where an object is located compared with a chosen starting point, called the origin. Displacement describes how far and in what direction the object has moved from its starting position.

These ideas help describe motion clearly. Position can change as an object moves. Displacement focuses on the change in position, not just the path taken. That makes it useful for comparing motion in a simple and precise way.

Tracking Motion with Position and Displacement

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Tracking Motion with Position and Displacement

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