Name: vectors in motion and direction
Uploaded: 2023-09-22T11:49:38.000Z
Duration: 1 min 21 s
Channel: JoVE

Las cantidades vectoriales son cantidades físicas que tienen magnitud y dirección.
La magnitud es el tamaño o la cantidad de una cantidad, y la dirección es la orientación en el espacio.
Por ejemplo, para abrir una puerta, se aplica una cierta cantidad de fuerza en una dirección particular. Por lo tanto, la fuerza es una cantidad vectorial.
El peso de cualquier objeto, que es la fuerza ejercida sobre un cuerpo debido a la gravedad, es una cantidad vectorial.
Los vectores se representan como letras en cursiva en negrita con una flecha encima de ellas. La magnitud se indica con el mismo símbolo vectorial entre barras verticales o mediante letras cursivas.
Geométricamente, los vectores se muestran mediante una línea con una flecha que señala su dirección y longitud que indica su magnitud.
El desplazamiento de un objeto de los puntos A a B se muestra con una flecha que se origina en A y termina en B y el vector se denota como vector D AB.

Dos vectores son iguales si tienen la misma magnitud y dirección.
El negativo de un vector se obtiene invirtiendo su dirección.
Si dos vectores apuntan en la misma dirección, son paralelos. Si apuntan en direcciones opuestas, son antiparalelos.

introducción a los vectores

Para definir algunas magnitudes físicas, es necesario especificar tanto la magnitud como la dirección. Por ejemplo, cuando la Guardia Costera de los Estados Unidos despacha un barco o un helicóptero para una misión de rescate, el equipo de rescate necesita saber no solo la distancia a la señal de socorro, sino también la dirección desde la cual proviene la señal, para poder llegar lo más rápido posible. Las magnitudes físicas especificadas completamente con un número de unidades (magnitud) y una dirección se llaman magnitudes vectoriales. Ejemplos de magnitudes vectoriales incluyen el desplazamiento, la velocidad, la posición, la fuerza y la torsión. En el lenguaje de las matemáticas, las magnitudes físicas vectoriales se representan mediante objetos matemáticos llamados vectores. Denotamos las magnitudes vectoriales con una letra en cursiva y un símbolo de flecha sobre ella. Una magnitud con solo magnitud y sin dirección es una magnitud escalar. Por lo tanto, el peso es una magnitud vectorial, mientras que la masa es una magnitud escalar. De manera similar, la rapidez es una magnitud escalar, mientras que la velocidad es una magnitud vectorial. Supongamos que le dices a un amigo en un viaje de acampada que has descubierto un gran lugar de pesca a 6 km de tu tienda de campaña. Es poco probable que tu amigo pueda encontrar fácilmente el lugar a menos que también le proporciones la dirección en la que se puede encontrar desde tu campamento. Podrías decir, por ejemplo, "Camina unos 6 km hacia el noreste desde mi tienda". El concepto clave aquí es que debes dar dos elementos de información, es decir, la distancia o magnitud (6 km) y la dirección (noreste). Un cambio de posición, como de la tienda de campaña al lugar de pesca en este ejemplo, se conoce como desplazamiento. Este es un ejemplo de una magnitud vectorial. Geométricamente, los vectores se representan como flechas; su longitud (que es un número positivo) da la magnitud, indicada al colocar la notación de valor absoluto alrededor del símbolo que denota el vector. El extremo de la flecha da la dirección y la punta de la flecha marca el punto final del vector. Dos vectores son iguales si y solo si tienen magnitudes iguales y la misma dirección. Dos vectores que tienen direcciones idénticas se denominan vectores paralelos, lo que significa que son paralelos entre sí. Sin embargo, si un vector apunta en la dirección opuesta, es decir, exactamente a 180° del primer vector, se dice que son antiparalelos. Dos vectores con direcciones mutuamente perpendiculares se denominan vectores ortogonales. Este texto está adaptado de <a href="https://openstax.org/books/university-physics-volume-1/pages/2-1-scalars-and-vectors">Openstax, University Physics Volume 1, Section 2.1: Scalars and Vectors.</a>

Introducción a los vectores

Para definir algunas cantidades físicas, es necesario especificar tanto la magnitud como la dirección. Por ejemplo, cuando la Guardia Costera de EE. UU. envía un ...

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Unit 1

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Physics Basics

Conceptos básicos de física

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TÉRMINOS Y CONCEPTOS CLAVE

Introduction to Vectors

vectors in motion and direction

Vectors describe quantities that have both size and direction. They are used in physics to show how motion, force, and other quantities act in space.

A vector can be represented with an arrow. The length of the arrow shows the size, and the arrowhead shows the direction. This makes vectors useful for comparing how one quantity points relative to another.

Scalars are different because they have size only and no direction. Understanding the difference between vectors and scalars is an important first step in physics. It helps students read motion and force problems more clearly.

Vectors in Motion and Direction

introduction to scalers

Scalar Quantities in Physics

Scalar quantities in physics have size only. They do not include direction. This makes them different from vector quantities. Common scalar examples include mass, temperature, time, and energy. Each one can be described with a number and a unit. Because direction is not part of the value, scalars are often easier to compare and measure.

vector or cross product

Cross Product of Two Vectors

The cross product of two vectors gives a new vector that is related to both original vectors. It is also called the vector product. In many physics problems, this operation helps describe quantities that depend on direction as well as size. The result of a cross product has a direction set by the two input vectors. It is not the same as ordinary multiplication. The transcript focuses on the vector or cross product as a core vector operation students use when working with vectors in science.

introduction to vectors

Vectors describe quantities that have both size and direction. They are used in physics to show how motion, force, and other quantities act in space. A vector can be represented with an arrow. The length of the arrow shows the size, and the arrowhead shows the direction. This makes vectors useful for comparing how one quantity points relative to another. Scalars are different because they have size only and no direction. Understanding the difference between vectors and scalars is an important...

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accuracy and precision

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position and displacement

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position and displacement vectors

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key terms and concepts

Learn how vectors show size and direction, how arrow length and arrowhead represent them, and how vectors differ from scalars in physics.

Vectors in Motion and Direction | JoVE K12

JoVE Core Mechanical Engineering offers concise, easy-to-understand animated videos covering key topics such as equilibrium, forces, truss analysis, and structural mechanics. Explore their real-world applications, and witness these concepts in action through scientist-led experiments.

mechanical engineering

Vectors in Motion and Direction

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