Name: couple moment in force systems
Uploaded: 2023-09-22T11:49:21.000Z
Duration: 1 min 29 s
Channel: JoVE

Bir çift, eşit büyüklüklere sahip ancak zıt yönlerde hareket eden, dik bir mesafe ile ayrılmış bir çift paralel kuvvettir.
Çift, vücudu kuvvetlerin düzlemine dik bir eksen etrafında döndüren bir dönme kuvvetine neden olur ve ortaya çıkan moment, çift momenti olarak bilinir.
Bir cıvatayı bijon anahtarıyla sıkmayı düşünün. Bir kuvvet çifti, A ve B noktalarında anahtara dik bir mesafe ile ayrılmış iki eşit ve zıt kuvvet uygulandığında oluşur.
rA ve rB konum vektörleri, bir koordinat sisteminin orijininden uygulama noktalarına yönlendirilir.
Orijin ile ilgili çift moment, konum vektörlerinin ve kuvvetlerin çapraz çarpımının toplamıdır.
rA ve rB konum vektörleri arasındaki fark, iki karşıt kuvvet arasındaki mesafe olan r konum vektörüdür.
Çift moment, rA ve rB konum vektörlerine değil, yalnızca kuvvetler arasındaki r konum vektörüne bağlıdır. Bu nedenle, ücretsiz bir vektör olarak kabul edilir.

<ol>
	<li>Hibbeler, R.C. (2016). Mühendislik Mekaniği \u2012 Statik ve Dinamik. Hoboken, New Jersey: Pearson Prentice Salonu. sayfa 154</li>
	<li>Bira, F.P.; Johnston, E.R.; Mazurek, D.F; Cromwell, P.J. ve Öz, B.P. (2019). Mühendisler için Vektör Mekaniği \u2012 Statik ve Dinamik. New York: McGraw-Tepesi. sayfa – 120.</li>
</ol>

kuvvet çifti

Bir çift mertebede eşit büyüklükte ve zıt yönlere sahip paralel kuvvetlerdir. Kuvvetler bir çiftin kol olarak adlandırılan dik uzaklıkla ayrılır. Çift, cismin kuvvetlerin düzlemine dik bir eksen etrafında dönme kuvveti veya moment oluşturur. Oluşan moment çift momenti olarak adlandırılır. Bir çift momentin SI birimi Newton-metre (N-m)'dir.

Bu kavramı anlamak için tipik bir örnek bir somunun bir lug anahtarıyla sıkıştırılmasıdır. Bir çift kuvvet, bir koordinat sistemine olan doğrultuları noktaları A ve B de anahtarın üzerine uygulanırken oluşur. İlgili konum vektörleri, noktanın uygulandığı yerden bir koordinat sisteminin kökenine doğru yönlendirilir. Köken çevresindeki çift moment, pozisyon vektörlerinin ve kuvvetlerin çapraz çarpımının toplamıdır. Zıt kuvvetlerin pozisyon vektörlerinin farkı, karşılıklı kuvvetler arasındaki mesafe olan r pozisyon vektörünü verir.

İlginçtir ki, çift momenti sadece kuvvetler arasındaki pozisyon vektörü r'e bağlıdır, iki kuvvetin bireysel pozisyon vektörlerine bağlı değildir. Pozisyon vektörü r kökenden bağımsızdır. Bu, aynı kuvvetlerin farklı noktalar etrafında momentlerinin aynı sonucu vereceği anlamına gelir. Çift momenti serbest bir vektördür. Bir çift momentin aksine, bir kuvvet momenti ölçüldüğü konuma bağlıdır. Eğer iki çift, büyüklük ve yönden eşit bir moment oluşturuyorsa, bu iki çift eşdeğerdir. Eşdeğer çiftler, pozisyonlarına, yönelimlerine veya büyüklüklerine bakılmaksızın eşit tork veya dönme etkilerine sahiptir.

Çift momentinin hesaplanması ve etkilerinin anlaşılması, dış kuvvetlere dayanabilen kararlı ve sağlam sistemlerin tasarımında önemlidir.

Bir çift, büyüklükte eşit ancak zıt yönlerde olan bir çift paralel kuvvettir. Kuvvetler, olarak bilinen dik bir mesafe ile ayrılır ...

Education

JoVE Core

Mechanical Engineering

Makine Mühendisliği

Unit 1

Ünite 1

Force System Resultants

Kuvvet Sistemleri Bileşkesi

KEY TERMS AND CONCEPTS

TEMEL TERİMLER VE KAVRAMLAR

Couple

couple moment in force systems

A couple is a pair of parallel forces that are equal in magnitude and opposite in direction. The two forces are separated by a perpendicular distance called the couple arm. Together, they create a turning effect on a body instead of a net push.

This turning effect is called the couple moment. It rotates the body about an axis that is perpendicular to the plane of the forces. The SI unit for a couple moment is the Newton-meter (N-m).

A common example is tightening a bolt with a lug wrench. In that case, two equal and opposite forces act at points A and B on the wrench. These points are separated by a perpendicular distance, so they form a force couple.

The couple moment about the origin is found by adding the cross products of the position vectors and the forces. The position vector between the two opposing forces is r, which is the distance between them. The couple moment depends only on this vector r, not on the separate position vectors of the forces.

Because r does not depend on the origin, the same couple moment is obtained even if the moments are taken about a different point. This is why a couple moment is a free vector. A moment of a single force is different because it depends on where it is measured.

If two couples create moments with the same magnitude and direction, they are equivalent couples. Equivalent couples have the same torque, or turning effect, even if their positions, directions, or magnitudes differ. Understanding couple moments helps in designing stable systems that can resist external forces.

Couple Moment in Force Systems

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cartesian form for vector formulation

Calculating Moment with Cartesian Vectors

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resultant moment: vector formulation

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principle of moments

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principle of moments: problem solving

Torque About an Axis in 3D Systems

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moment of a force about an axis: vector

Torque on a Bicycle Wheel: Vector Method

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couple

A couple is a pair of parallel forces that are equal in magnitude and opposite in direction. The two forces are separated by a perpendicular distance called the couple arm. Together, they create a turning effect on a body instead of a net push. This turning effect is called the couple moment. It rotates the body about an axis that is perpendicular to the plane of the forces. The SI unit for a couple moment is the Newton-meter (N-m). A common example is tightening a bolt with a lug wrench. In...

couples: scalar and vector formulation

Couple Moments and the Right-Hand Rule

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equivalent couples

Equivalent Couples in Mechanical Systems

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moment of a couple: problem solving

Torque from a Couple: Solving Forces

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Equivalent Force and Moment Systems

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simplification of a force and couple system i

simplification-of-a-force-and-couple-system-i

Resultant Forces in Force and Couple Systems

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simplification of a force and couple system: ii

simplification-of-a-force-and-couple-system-ii

Resultant Force and Wrench Motion

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key terms and concepts

Learn how a couple creates rotation, why couple moment depends on the distance between forces, and how equivalent couples are identified in force systems.

Couple Moment in Force Systems | JoVE K12

JoVE Core Makine Mühendisliği, denge, kuvvetler, kafes kiriş analizi ve yapısal mekanik gibi temel konuları kapsayan kısa, anlaşılması kolay animasyonlu videolar sunar. Gerçek dünyadaki uygulamalarını keşfedin ve bilim insanlarının önderlik ettiği deneylerle bu kavramların uygulanmasına tanık olun.

mechanical engineering

Couple Moment in Force Systems

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