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

Das Drehmoment oder das Moment einer Kraft ist die Fähigkeit einer Kraft, einen Körper um einen Punkt oder eine Achse zu drehen, die sich nicht in der Wirkungslinie der Kraft befindet. Es handelt sich um eine Vektorgröße.
Betrachten Sie ein Beispiel für ein Schwungrad, bei dem eine Kraft ausgeübt wird, um das Schwungrad um den Punkt O zu drehen.
Hier ist der Momentenarm der senkrechte Abstand vom Punkt O zur Wirkungslinie der Kraft.
Die Größe der Kraft wird mit dem Momentenarm multipliziert, um die Größe des Moments zu erhalten. Die Einheit für das Moment einer Kraft ist also Newtonmeter.
Seine Größe ist maximal, wenn die aufgebrachte Kraft tangential zum Schwungrad ist.
Die Rechts-Hand-Regel wird verwendet, um die Richtung des Augenblicks zu bestimmen. Wenn die gekrümmten Finger die durch den Moment verursachte Drehung darstellen, dann stellt der Daumen die Richtung des Augenblicks dar.
Herkömmlicherweise bezeichnet das positive Moment die Umdrehung gegen den Uhrzeigersinn, während das negative Vorzeichen die Umdrehung des Schwungrads im Uhrzeigersinn bezeichnet.

<ol>
	<li>Hibbeler, R.C. (2016). Technische Mechanik \u2012 Statik und Dynamik. Hoboken, New Jersey: Pearson Prentice Hall. S. 121 \u2012 122.</li>
</ol>

moment einer kraft: skalare formulierung

Der Moment einer Kraft, auch bekannt als Drehmoment, misst die Fähigkeit der Kraft, in einem Körper um eine Achse eine Drehbewegung zu erzeugen. Es handelt sich um eine Vektorgröße, was bedeutet, dass sie sowohl einen Betrag als auch eine Richtung hat. Dieses Konzept wird in der Ingenieurwissenschaft, Physik und Mechanik umfassend verwendet. Betrachten Sie ein einfaches Beispiel eines Schwungrades, das um einen Punkt O rotiert wird, indem eine Kraft auf es ausgeübt wird. In diesem Fall ist der Momentenarm der senkrechte Abstand zwischen dem Punkt O und der Wirkungslinie der Kraft. Der Betrag des Moments wird berechnet, indem der Betrag der Kraft mit dem Momentenarm multipliziert wird. Diese Größe hat die Einheit Newton-Meter (N-m). Das maximale Moment tritt auf, wenn die angewandte Kraft tangential zum Schwungrad ist, da sie senkrecht zum Radius des Schwungrads steht. Der Betrag des Moments nimmt auch mit dem Betrag der angewendeten Kraft und der Länge des Momentenarms zu. Die Rechte-Hand-Regel bestimmt die Richtung des Moments. Wenn sich die Finger der rechten Hand in Richtung der Drehbewegung krümmen, die durch das Moment erzeugt wird, zeigt der Daumen in Richtung des Moments. Konventionell deutet ein positives Moment auf eine gegen den Uhrzeigersinn gerichtete Drehbewegung hin, während ein negatives Vorzeichen auf eine im Uhrzeigersinn gerichtete Drehbewegung hinweist. Der Moment einer Kraft ist wesentlich für das Verständnis der Dynamik von Maschinen und Strukturen. Er ist ein wichtiges Werkzeug zur Analyse und Vorhersage des Verhaltens komplexer mechanischer Systeme.

Moment einer Kraft: Skalare Formulierung

Das Moment einer Kraft, auch Drehmoment genannt, misst die Fähigkeit der Kraft, eine Rotationsbewegung in einem Körper um eine Achse zu erzeugen. Es ist ein Vektor ...

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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

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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.

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Torque on a Flywheel: Direction and Size

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