Name: bicycle torque and moment about an axis
Uploaded: 2023-09-22T11:49:21.000Z
Duration: 1 min 28 s
Channel: JoVE

Considere a un ciclista que monta en bicicleta y aplica fuerza en el pedal para girar la rueda. Cuando se ejerce una fuerza sobre el pedal, la cadena adjunta ejerce una fuerza sobre los engranajes de la rueda. La rueda gira alrededor de su eje, por lo que el eje de rotación pasa a través de ella.
El momento de una fuerza a lo largo del eje mide cuánto hace que la fuerza haga que un objeto gire alrededor de un punto o eje específico.
En este caso, la rueda gira alrededor del eje y en el plano x-z. Aquí, el brazo de momento o la distancia perpendicular entre el eje de rotación y la línea de acción de la fuerza es el radio de los engranajes.
Por lo tanto, el momento de una fuerza alrededor del eje y es igual a Frsinθ.
Dado que la fuerza es tangencial, el ángulo entre el vector de fuerza y el radio es de 90 grados.
En una bicicleta, el momento de fuerza se puede multiplicar por la velocidad angular del eje para obtener la potencia generada por la rotación de la rueda.

<ol>
	<li>Hibbeler, R.C. (2016). Ingeniería Mecánica \u2012 Estática y Dinámica. Hoboken, Nueva Jersey: Pearson Prentice Hall. Págs. 145.</li>
</ol>

momento de una fuerza alrededor de un eje: escalar

Moment of a Force About an Axis: Scalar

El momento de una fuerza alrededor de un eje es un concepto crucial en la mecánica que ayuda a determinar el movimiento de rotación de un objeto alrededor de un punto o eje específico. El momento de la fuerza se puede calcular utilizando análisis escalar, lo cual implica considerar la distancia perpendicular entre el eje de rotación y la línea de acción de la fuerza o simplemente el brazo del momento. Para entender mejor el concepto del momento de la fuerza, consideremos el ejemplo de un ciclista montando en una bicicleta. Cuando el ciclista aplica fuerza al pedal, la cadena conectada ejerce una fuerza sobre el eje de la rueda, causando que esta rote. Aquí, el eje de rotación pasa a través del eje de la rueda y el brazo del momento es el radio del eje. En este caso, el momento de la fuerza alrededor del eje de rotación se calcula mediante la siguiente fórmula: <img alt="Equation 1" src="/files/ftp_upload/14258/14258_Equation_1v2.svg" style="text-align: center; height: 13px;"> donde, F es la fuerza aplicada, r es el radio del eje, y θ es el ángulo entre el vector de fuerza y el radio. Dado que la fuerza es tangencial, el ángulo entre el vector de fuerza y el radio es de 90 grados. En una bicicleta, el momento de la fuerza se puede multiplicar por la velocidad angular del eje para obtener la potencia generada por la rotación de la rueda. El momento de la fuerza es esencial en el diseño de varias estructuras y máquinas, incluyendo bicicletas, automóviles y aviones, para asegurar su estabilidad y seguridad.

Momento de una fuerza alrededor de un eje: Escalar

El momento de una fuerza alrededor de un eje es un concepto crucial en mecánica que ayuda a determinar el movimiento de rotación de un objeto alrededor de un punto específico o ...

Education

Educación

JoVE Core

Mechanical Engineering

Ingeniería Mecánica

Unit 1

Unidad 1

Force System Resultants

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KEY TERMS AND CONCEPTS

TÉRMINOS Y CONCEPTOS CLAVE

bicycle torque and moment about an axis

The moment of a force about an axis describes how a force can make an object turn around a fixed line. In scalar analysis, the moment is found from the perpendicular distance between the axis of rotation and the line of action of the force. That distance is called the moment arm.

A bicycle gives a clear example of this idea. When the cyclist pushes on the pedal, the chain applies a force to the wheel’s axle and makes it rotate. The axis of rotation passes through the axle, and the moment arm is the axle radius.

For this case, the moment of force about the axis depends on the force, the radius, and the angle between the force vector and the radius. Because the force is tangential, that angle is 90 degrees. The moment of force can also be multiplied by the angular velocity of the axle to find the power produced by the wheel rotation.

This concept is important in the design of bicycles, automobiles, and aircraft. Engineers use it to help maintain stability and safety in these machines and structures.

Bicycle Torque and Moment About an Axis

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Learn how the moment of a force about an axis is found with scalar analysis, using a bicycle axle example and its link to rotational power.

Bicycle Torque and Moment About an Axis | JoVE K12

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Bicycle Torque and Moment About an Axis

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