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

Stellen Sie sich einen Radfahrer vor, der ein Fahrrad fährt und Kraft auf das Pedal ausübt, um das Rad zu drehen. Wenn eine Kraft auf das Pedal ausgeübt wird, übt die daran befestigte Kette eine Kraft auf die Zahnräder des Rades aus. Das Rad dreht sich um seine Achse, so dass die Drehachse durch sie verläuft.
Das Moment einer Kraft entlang der Achse misst, wie stark die Kraft dazu führt, dass sich ein Objekt um einen bestimmten Punkt oder eine bestimmte Achse dreht.
In diesem Fall dreht sich das Rad um die y-Achse in der x-z-Ebene. Dabei ist der Momentenarm bzw. der senkrechte Abstand zwischen der Drehachse und der Wirkungslinie der Kraft der Radius der Zahnräder.
Das Moment einer Kraft um die y-Achse ist also gleich Frsinθ.
Da die Kraft tangential ist, beträgt der Winkel zwischen dem Kraftvektor und dem Radius 90 Grad.
Bei einem Fahrrad kann das Kraftmoment mit der Winkelgeschwindigkeit der Achse multipliziert werden, um die durch die Raddrehung erzeugte Kraft zu erhalten.

<ol>
	<li>Hibbeler, R.C. (2016). Technische Mechanik \u2012 Statik und Dynamik. Hoboken, New Jersey: Pearson Prentice Hall. S. 145.</li>
</ol>

moment einer kraft um eine achse: skalar

Moment of a Force About an Axis: Scalar

Der Moment einer Kraft um eine Achse ist ein entscheidendes Konzept in der Mechanik, das dabei hilft, die Drehbewegung eines Objekts's um einen bestimmten Punkt oder eine Achse zu bestimmen. Der Moment einer Kraft kann mithilfe von Skalaranalyse berechnet werden, bei der der senkrechte Abstand zwischen der Rotationsachse und der Wirkungslinie der Kraft oder einfach der Momentarm berücksichtigt wird. Um das Konzept des Momentes einer Kraft besser zu verstehen, betrachten wir das Beispiel eines Radfahrers auf einem Fahrrad. Wenn der Radfahrer Kraft auf das Pedal ausübt, wirkt die angebrachte Kette eine Kraft auf die Achse des Rads aus, wodurch es sich dreht. Hier verläuft die Rotationsachse durch die Achse des Rads und der Momentarm ist der Radius der Achse. In diesem Fall wird der Moment der Kraft um die Rotationsachse wie folgt gegeben: <img alt="Equation 1" src="/files/ftp_upload/14258/14258_Equation_1v2.svg" style="text-align: center; height: 13px;"> wo F die ausgeübte Kraft ist, r der Radius der Achse und θ der Winkel zwischen dem Kraftvektor und dem Radius ist. Da die Kraft tangential ist, beträgt der Winkel zwischen dem Kraftvektor und dem Radius 90 Grad. In einem Fahrrad kann der Moment der Kraft mit der Winkelgeschwindigkeit der Achse multipliziert werden, um die von der Raddrehung erzeugte Leistung zu erhalten. Der Moment der Kraft ist essentiell für das Design verschiedener Strukturen und Maschinen, einschließlich Fahrrädern, Autos und Flugzeugen, um ihre Stabilität und Sicherheit zu gewährleisten.

Moment einer Kraft um eine Achse: Skalar

Das Moment einer Kraft um eine Achse ist ein entscheidendes Konzept in der Mechanik, das hilft, die Rotationsbewegung eines Objekts um einen bestimmten Punkt oder ...

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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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