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

Wyobraźmy sobie rowerzystę jadącego na rowerze i przykładającego siłę do pedału, aby obrócić koło. Kiedy na pedał wywierana jest siła, dołączony łańcuch wywiera siłę na zębatki koła. Koło obraca się wokół własnej osi, więc oś obrotu przechodzi przez nie.
Moment siły wzdłuż osi mierzy, jak bardzo siła powoduje obrót obiektu wokół określonego punktu lub osi.
W tym przypadku koło obraca się wokół osi y w płaszczyźnie x-z. W tym przypadku ramieniem momentu lub prostopadłą odległością między osią obrotu a linią działania siły jest promień kół zębatych.
Zatem moment siły wokół osi y jest równy Frsinθ.
Ponieważ siła jest styczna, kąt między wektorem siły a promieniem wynosi 90 stopni.
W rowerze moment siły można pomnożyć przez prędkość kątową osi, aby uzyskać moc generowaną przez obrót koła.

<ol>
	<li>Hibbeler, R.C. (2016). Mechanika inżynierska \u2012 Statyka i dynamika. Hoboken, New Jersey: Pearson Prentice Hall. str. 145.</li>
</ol>

moment siły wokół osi: skalar

Moment of a Force About an Axis: Scalar

Moment siły wokół osi to pojęcie w mechanice, które pozwala określić ruch obrotowy obiektu wokół określonego punktu lub osi. Moment siły można obliczyć za pomocą analizy skalarnej, która polega na uwzględnieniu prostopadłego odległości między osią obrotu a linią działania siły, lub po prostu ramieniem momentu.

Aby lepiej zrozumieć pojęcie momentu siły, rozważmy przykład jadącego na rowerze rowerzysty. Kiedy rowerzysta naciska na pedał, łańcuch wywiera siłę na oś koła, powodując jego obroty. Tutaj oś obrotu przechodzi przez środek koła, a ramieniem momentu jest promień osi. W tym przypadku moment siły wokół osi obrotu jest określany wzorem:

<img alt="Equation 1" src="/files/ftp_upload/14258/14258_Equation_1v2.svg" style="text-align: center; height: 13px;" />

Gdzie F to przyłożona siła, r to promień osi, a θ to kąt między wektorem siły a promieniem osi. Ponieważ siła jest styczna, kąt między wektorem siły a promieniem wynosi 90 stopni.

W rowerze moment siły można pomnożyć przez prędkość kątową osi, aby obliczyć moc generowaną przez obroty koła. Moment siły jest istotny przy projektowaniu różnych konstrukcji i maszyn, w tym rowerów, samochodów i samolotów, w celu zapewnienia ich stabilności i bezpieczeństwa.

Moment siły wokół osi: skalar

Moment siły wokół osi jest kluczowym pojęciem w mechanice, które pomaga określić ruch obrotowy obiektu wokół określonego punktu lub ...

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Mechanical Engineering

Inżynieria mechaniczna

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Force System Resultants

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KEY TERMS AND CONCEPTS

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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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key terms and concepts

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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