Name: torque on a flywheel: direction and size
Uploaded: 2023-09-22T11:49:20.000Z
Duration: 1 min 18 s
Channel: JoVE

El par, o el momento de una fuerza, es la capacidad de una fuerza para hacer girar un cuerpo alrededor de un punto o un eje que no está en la línea de acción de la fuerza. Es una cantidad vectorial.
Considere un ejemplo de un volante de inercia, donde se aplica una fuerza para girar el volante alrededor del punto O.
Aquí, el brazo de momento es la distancia perpendicular desde el punto O hasta la línea de acción de la fuerza.
La magnitud de la fuerza se multiplica por el brazo del momento para obtener la magnitud del momento. Por lo tanto, la unidad para el momento de una fuerza es newton-metro.
Su magnitud es máxima cuando la fuerza aplicada es tangencial al volante de inercia.
La regla de la mano derecha se utiliza para determinar la dirección del momento. Si los dedos curvados representan la rotación causada por el momento, entonces el pulgar representa la dirección del momento.
Convencionalmente, el momento positivo denota la rotación en sentido contrario a las agujas del reloj, mientras que el signo negativo denota la rotación del volante en el sentido de las agujas del reloj.

<ol>
	<li>Hibbeler, R.C. (2016). Ingeniería Mecánica \u2012 Estática y Dinámica. Hoboken, Nueva Jersey: Pearson Prentice Hall. págs. 121 \u2012 122.</li>
</ol>

momento de una fuerza: formulación escalar

El momento de una fuerza, también conocido como torque, mide la capacidad de la fuerza para crear movimiento de rotación en un cuerpo alrededor de un eje. Es una cantidad vectorial, lo que significa que tiene tanto magnitud como dirección. Este concepto se utiliza ampliamente en ingeniería, física y mecánica. Consideremos un ejemplo simple de un volante que se gira alrededor de un punto, O, aplicando una fuerza sobre él. En este caso, el brazo de momento es la distancia perpendicular entre el punto O y la línea de acción de la fuerza. La magnitud del momento se calcula multiplicando la magnitud de la fuerza por el brazo de momento. Esta cantidad tiene la unidad de newton-metro (N-m). El momento máximo ocurre cuando la fuerza aplicada es tangente al volante, ya que es perpendicular al radio del volante. La magnitud del momento también aumenta con la magnitud de la fuerza aplicada y la longitud del brazo de momento. La regla de la mano derecha determina la dirección del momento. Si los dedos de la mano derecha se curvan en la dirección del movimiento de rotación producido por el momento, entonces el pulgar apunta en la dirección del momento. Convencionalmente, un momento positivo denota un movimiento de rotación en sentido contrario a las agujas del reloj, mientras que un signo negativo denota un movimiento de rotación en sentido de las agujas del reloj. El momento de una fuerza es esencial para comprender la dinámica de máquinas y estructuras. Es una herramienta crítica para analizar y predecir el comportamiento de sistemas mecánicos complejos.

Momento de una fuerza: Formulación escalar

El momento de una fuerza, también conocido como par, mide la capacidad de la fuerza para crear un movimiento de rotación en un cuerpo alrededor de un eje. Es un vector ...

Education

Educación

JoVE Core

Mechanical Engineering

Ingeniería Mecánica

Unit 1

Unidad 1

Force System Resultants

Resultantes de Sistemas de Fuerzas

KEY TERMS AND CONCEPTS

TÉRMINOS Y CONCEPTOS CLAVE

Moment of a Force: Scalar Formulation

torque on a flywheel: direction and size

Torque, or the moment of a force, describes how a force can make an object turn about an axis. It is a vector quantity, so it has both size and direction. This idea is important in physics, mechanics, and engineering.

A simple flywheel example shows how torque works. The flywheel rotates about point O when a force is applied to it. The moment arm is the perpendicular distance from point O to the line of action of the force. The moment, in newton-meter (N-m), is found by multiplying the force by the moment arm.

The largest moment happens when the force acts tangentially to the flywheel. In that case, the force is perpendicular to the radius of the flywheel. The moment also gets larger when the applied force is larger or when the moment arm is longer.

The right-hand rule gives the direction of the moment. If the fingers of the right hand curl in the direction of the rotation, the thumb points along the moment direction. By convention, counterclockwise motion is positive, and clockwise motion is negative. This helps in analyzing machines and structures and in predicting how mechanical systems behave.

Torque on a Flywheel: Direction and Size

moment of a force: scalar formulation

Torque, or the moment of a force, describes how a force can make an object turn about an axis. It is a vector quantity, so it has both size and direction. This idea is important in physics, mechanics, and engineering. A simple flywheel example shows how torque works. The flywheel rotates about point O when a force is applied to it. The moment arm is the perpendicular distance from point O to the line of action of the force. The moment, in newton-meter (N-m), is found by multiplying the force...

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key terms and concepts

Learn how torque, or moment of a force, depends on force size, moment arm length, and direction using a flywheel example and the right-hand rule.

Torque on a Flywheel: Direction and Size | 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

Torque on a Flywheel: Direction and Size

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