Name: scalar vs vector quantities in mechanics
Uploaded: 2023-09-22T11:49:38.000Z
Duration: 1 min 22 s
Channel: JoVE

Varias cantidades físicas en mecánica de ingeniería utilizadas para describir el movimiento del objeto se miden utilizando escalares o vectores.
Los escalares son cantidades físicas que se describen por magnitud y se representan mediante un valor numérico con una unidad física, ya sea positiva o negativa. La longitud, la velocidad, la distancia y el tiempo son algunos ejemplos.
Los vectores son cantidades físicas que se describen mediante una flecha que tiene magnitud y dirección. La longitud de la flecha representa la magnitud, y el ángulo entre el vector y un eje fijo representa la dirección de su línea de acción.
Se representan en negrita, o con la ayuda de una flecha sobre la letra, mientras que sus magnitudes se representan en cursiva con la letra. Algunos ejemplos son la velocidad, la aceleración y la fuerza.
Por ejemplo, considere un ascensor móvil. Las dimensiones y la masa del ascensor son las cantidades escalares, mientras que la velocidad y el peso del ascensor son cantidades vectoriales, ya que tienen una magnitud y una dirección.

<ol>
	<li>Hibbeler, R.C. (2016). Ingeniería Mecánica \u2012 Estática y Dinámica. Hoboken, Nueva Jersey: Pearson Prentice Hall. págs. 17</li>
</ol>

escalar y vectores

En mecánica, términos comúnmente utilizados como fuerza, velocidad, velocidad y trabajo se pueden clasificar como cantidades escalares o vectoriales. Un escalar es una cantidad física que se puede describir solo por su magnitud y no requiere ningún componente direccional. Ejemplos de cantidades escalares son masa, área y longitud. Las cantidades escalares con las mismas unidades físicas se pueden sumar o restar de acuerdo con las reglas algebraicas habituales para los números. Por ejemplo, una clase que termina 10 minutos antes que otra clase de 50 minutos dura 50 minutos - 10 minutos = 40 minutos. De manera similar, una porción de maíz de 60 calorías seguida de una porción de donas de 200 calorías da como resultado 60 calorías + 200 calorías = 260 calorías de energía. Cuando multiplicamos una cantidad escalar por un número, obtenemos la misma cantidad escalar pero con un valor más grande (o más pequeño). Por ejemplo, si el desayuno de ayer tenía 200 calorías de energía y el desayuno de hoy tiene cuatro veces más energía que el de ayer, entonces el desayuno de hoy tiene 4 x 200 calorías = 800 calorías de energía. Dos cantidades escalares también se pueden multiplicar o dividir entre sí para formar una cantidad escalar derivada. Por ejemplo, si un tren recorre una distancia de 120 km en 1 hora, su velocidad es de 120,000 m / 3600 s = 33 m/s, donde la velocidad es una cantidad escalar derivada obtenida dividiendo la distancia entre el tiempo. Por otro lado, una cantidad vectorial es una cantidad física que tiene tanto magnitud como dirección. Un vector se puede representar gráficamente utilizando una flecha. La longitud de la flecha simboliza la magnitud del vector, mientras que el ángulo entre la flecha y un eje fijo determina su dirección de acción. La punta de la flecha representa la dirección en la que apunta el vector. Ejemplos de cantidades vectoriales incluyen desplazamiento, velocidad, posición, fuerza y torque. Considera dar indicaciones a un amigo en un viaje de senderismo para un punto de descanso a 6 km de la tienda de campaña. La forma más fácil será identificar en qué dirección llegar a la ubicación exacta; por ejemplo, 6 km al sureste será más útil. Esta cantidad es el desplazamiento del excursionista. Dos vectores son iguales si tienen magnitudes iguales y la misma dirección. Dos vectores con direcciones idénticas se denominan vectores paralelos. Sin embargo, si un vector apunta en dirección opuesta, exactamente 180°, al primer vector, se dice que son antiparalelos. Dos vectores con direcciones perpendiculares entre sí se denominan vectores ortogonales.

Escalar y Vectores

En mecánica, los términos de uso común como fuerza, velocidad, velocidad y trabajo se pueden clasificar como cantidades escalares o vectoriales. Un escalar es un ...

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Scalar and Vectors

scalar vs vector quantities in mechanics

Scalar and vector quantities are two main ways to describe physical quantities in mechanics. Common examples include force, speed, velocity, and work. Some of these are scalars, and others are vectors.

A scalar is a quantity that has magnitude only. It does not need direction. Mass, area, and length are examples of scalar quantities. Scalars with the same units can be added or subtracted like ordinary numbers. A class that ends 10 min earlier than 50 min lasts 50 min minus 10 min, which is 40 min.

Scalars can also be multiplied by a number. If yesterday’s breakfast had 200 calories of energy and today’s breakfast has four times as much, then today’s breakfast has 800 calories of energy. Two scalars can also be multiplied or divided to make another scalar quantity. For example, a train that covers 120 km in 1 h has a speed of 120,000 m/3600 s, or 33 m/s. That speed is a derived scalar quantity.

A vector has both magnitude and direction. Vectors are often shown with arrows. The arrow length shows the magnitude. The angle with a fixed axis shows the line of action, and the arrowhead shows the direction. Displacement, velocity, position, force, and torque are examples of vector quantities.

Direction matters in everyday situations. If a hiking rest point is 6 km from a tent, saying 6 km southeast is more useful than saying only 6 km. That gives the hiker displacement, which is a vector. Two vectors are equal if they have the same magnitude and the same direction. Vectors with the same direction are parallel. Vectors that point exactly 180° apart are antiparallel. Vectors that meet at right angles are orthogonal.

Scalar vs Vector Quantities in Mechanics

scalar and vectors

Scalar and vector quantities are two main ways to describe physical quantities in mechanics. Common examples include force, speed, velocity, and work. Some of these are scalars, and others are vectors. A scalar is a quantity that has magnitude only. It does not need direction. Mass, area, and length are examples of scalar quantities. Scalars with the same units can be added or subtracted like ordinary numbers. A class that ends 10 min earlier than 50 min lasts 50 min minus 10 min, which is 40...

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Scalar vs Vector Quantities in Mechanics

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