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

자전거를 타는 사람이 페달에 힘을 가하여 바퀴를 돌린다고 생각해 보십시오. 페달에 힘이 가해지면 부착된 체인이 휠의 톱니바퀴에 힘을 가합니다. 휠은 축을 중심으로 회전하므로 회전축이 휠을 통과합니다.
축을 따라 가해지는 힘의 모멘트는 힘으로 인해 물체가 특정 점 또는 축을 중심으로 회전하는 정도를 측정합니다.
이 경우 휠은 x-z 평면의 y축을 기준으로 회전합니다. 여기서 모멘트 암 또는 회전축과 힘의 작용선 사이의 수직 거리는 톱니바퀴의 반지름입니다.
따라서 y축에 대한 힘의 모멘트는 Frsinθ와 같습니다.
힘은 접선이므로 힘 벡터와 반지름 사이의 각도는 90도입니다.
자전거에서 힘의 모멘트에 차축의 각속도를 곱하여 바퀴 회전에 의해 생성된 동력을 얻을 수 있습니다.

<ol>
	<li>히벨러, R.C. (2016). Engineering Mechanics \u2012 정역학 및 동역학. 뉴저지 호보켄: 피어슨 프렌티스 홀. 145쪽.</li>
</ol>

축에 대한 힘의 모멘트: 스칼라

Moment of a Force About an Axis: Scalar

축에 대한 힘의 모멘트는 역학에서 특정한 점이나 축을 중심으로 회전하는 물체의 운동을 결정하는 데 도움이 되는 중요한 개념입니다. 힘의 모멘트는 회전축과 힘의 작용선 사이의 수직거리를 고려하는 스칼라 분석을 사용하여 계산할 수 있습니다.

힘의 모멘트 개념을 더 잘 이해하려면 자전거를 타는 사이클리스트의 예를 생각해 보세요. 사이클리스트가 페달에 힘을 가하면 연결된 체인이 바퀴의 차축에 힘을 가하여 회전하게 합니다. 여기서 회전축은 바퀴의 차축을 통과하고 모멘트 암은 차축의 반지름입니다. 이 경우 회전축에 대한 힘의 모멘트는 다음과 같습니다:

<img alt="Equation 1" src="/files/ftp_upload/14258/14258_Equation_1v2.svg" style="text-align: center; height: 13px;" />

여기서 F은 가해진 힘, r은 차축의 반지름, θ은 힘 벡터와 반지름 사이의 각도입니다. 힘이 접선 방향이므로 힘 벡터와 반지름 사이의 각도는 90도입니다.

자전거에서는 차축의 각속도에 힘의 모멘트를 곱하여 바퀴의 회전에 의해 발생하는 동력을 얻을 수 있습니다. 힘의 모멘트는 자전거, 자동차, 항공기를 포함한 다양한 구조물과 기계의 안정성과 안전성을 확보하기 위해 설계하는 데 필수적입니다.

축에 대한 힘의 모멘트는 특정 지점 또는 ...

Education

교육

JoVE Core

Mechanical Engineering

기계공학

Unit 1

제1단원

Force System Resultants

힘 체계의 합력

KEY TERMS AND CONCEPTS

주요 용어 및 개념

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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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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Resultant moment describes the total turning effect of multiple forces acting on an object. It shows how several forces can combine to make a body rotate about a point. In physics, moment is the tendency of a force to cause rotation. The resultant moment of a force system is a vector quantity. That means it can be added and subtracted like other vectors. For a system with two forces, F1 and F2, acting on a pole at points A and B, the resultant moment is written as MR = (rA x F1) + (rB x F2).

principle of moments

Resolving Forces in Moment Calculations

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moment of a force about an axis: scalar

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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

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.

mechanical engineering

Bicycle Torque and Moment About an Axis

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