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

Представьте себе велосипедиста, едущего на велосипеде и прикладывающего усилие к педали, чтобы повернуть руль. Когда на педаль прилагается усилие, прикрепленная цепь прилагает усилие к зубьям колеса. Колесо вращается вокруг своей оси, поэтому ось вращения проходит через него.
Момент силы вдоль оси измеряет, насколько эта сила заставляет объект вращаться вокруг определенной точки или оси.
В этом случае колесо вращается вокруг оси y в плоскости x-z. Здесь плечо момента или перпендикулярное расстояние между осью вращения и линией действия силы является радиусом зубцов.
Таким образом, момент силы вокруг оси y равен Frsinθ.
Поскольку сила является тангенциальной, угол между вектором силы и радиусом составляет 90 градусов.
В велосипеде момент силы можно умножить на угловую скорость оси, чтобы получить мощность, создаваемую вращением колеса.

<ol>
	<li>Хиббелер, Р.К. (2016). Инженерная механика \u2012 Статика и динамика. Хобокен, Нью-Джерси: Пирсон Прентис Холл. С. 145.</li>
</ol>

Момент силы относительно оси: скаляр

Moment of a Force About an Axis: Scalar

Момент силы относительно оси - это важное понятие в механике, которое помогает определить вращательное движение объекта вокруг определенной точки или оси. Момент силы может быть вычислен с помощью скалярного анализа, который включает рассмотрение перпендикулярного расстояния между осью вращения и линией действия силы или просто момента силы.

Для лучшего понимания понятия момента силы рассмотрим пример велосипедиста, едущего на велосипеде. Когда велосипедист давит на педаль, цепь передаёт силу на ось колеса, вызывая его вращение. Здесь ось вращения проходит через ось колеса, а момент силы представляет собой радиус оси. В этом случае момент силы относительно оси вращения выражается следующим образом:

<img alt="Equation 1" src="/files/ftp_upload/14258/14258_Equation_1v2.svg" style="text-align: center; height: 13px;" />

где F - приложенная сила, r - радиус оси, а θ - угол между вектором силы и радиусом. Поскольку сила тангенциальна, угол между вектором силы и радиусом составляет 90 градусов.

В велосипеде момент силы может быть умножен на угловую скорость оси, чтобы получить мощность, производимую вращением колеса. Момент силы является важным при проектировании различных конструкций и механизмов, включая велосипеды, автомобили и самолеты, чтобы обеспечить их стабильность и безопасность.

Момент действия силы вокруг оси является ключевым понятием в механике, которое помогает определить вращательное движение объекта вокруг определенной точки или ...

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Mechanical Engineering

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Unit 1

Раздел 1

Force System Resultants

Результирующие силы системы

KEY TERMS AND CONCEPTS

ОСНОВНЫЕ ТЕРМИНЫ И ПОНЯТИЯ

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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