Name: torque on a flywheel: direction and size
Uploaded: 2023-09-22T11:49:20.000Z
Duration: 1 min 18 s
Channel: JoVE

Moment obrotowy lub moment siły to zdolność siły do obracania ciała wokół punktu lub osi, która nie znajduje się na linii działania siły. Jest to wielkość wektorowa.
Rozważmy przykład koła zamachowego, w którym przykładana jest siła, aby obrócić koło zamachowe wokół punktu O.
Tutaj ramię momentu jest prostopadłą odległością od punktu O do linii działania siły.
Wielkość siły mnoży się przez ramię momentu, aby uzyskać wielkość momentu. Tak więc jednostką momentu siły jest niutonometr.
Jego wielkość jest maksymalna, gdy przyłożona siła jest styczna do koła zamachowego.
Reguła prawej ręki służy do określania kierunku momentu. Jeśli zgięte palce reprezentują obrót spowodowany momentem, to kciuk reprezentuje kierunek momentu.
Konwencjonalnie moment dodatni oznacza obrót w kierunku przeciwnym do ruchu wskazówek zegara, podczas gdy znak ujemny oznacza obrót koła zamachowego w kierunku zgodnym z ruchem wskazówek zegara.

<ol>
	<li>Hibbeler, R.C. (2016). Mechanika inżynierska \u2012 Statyka i dynamika. Hoboken, New Jersey: Pearson Prentice Hall. str. 121 \u2012 122.</li>
</ol>

moment siły: formuła skalarna

Moment siły, znany również jako moment obrotowy, mierzy zdolność siły do tworzenia ruchu obrotowego ciała wokół osi. Jest to wielkość wektorowa, co oznacza, że ma zarówno wartość bezwzględną, jak i kierunek. To pojęcie jest szeroko stosowane w inżynierii, fizyce i mechanice.

Przyjrzyjmy się prostemu przykładowi wirnika obracanego wokół punktu O za pomocą siły. W tym przypadku, ramię momentu jest prostopadłą odległością między punktem O a linią działania siły. Wartość bezwzględna momentu jest obliczana poprzez pomnożenie wartości bezwzględnej siły przez ramię momentu. Ta wielkość ma jednostkę newton-metr (N-m).

Maksymalny moment występuje, gdy siła jest styczna do wirnika, ponieważ jest prostopadła do promienia wirnika. Wartość bezwzględna momentu również wzrasta wraz z wartością siły zastosowanej i długością ramienia momentu.

Reguła prawej ręki określa kierunek momentu. Jeżeli palce prawej ręki zamykają się w kierunku ruchu obrotowego wywołanego przez moment, to kciuk wskazuje kierunek momentu. Konwencjonalnie, dodatni moment oznacza ruch przeciwnie do ruchu wskazówek zegara, podczas gdy ujemny znak oznacza ruch zgodny z ruchem wskazówek zegara.

Moment siły jest niezbędny do zrozumienia dynamiki maszyn oraz konstrukcji. Jest to kluczowe narzędzie do analizy oraz przewidywania zachowania skomplikowanych układów mechanicznych.

Moment siły: Formuła skalarna

Moment siły, znany również jako moment obrotowy, mierzy zdolność siły do wytworzenia ruchu obrotowego w ciele wokół osi. Jest to wektor ...

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JoVE Core

Mechanical Engineering

Inżynieria mechaniczna

Unit 1

Jednostka 1

Force System Resultants

wypadkowe układu sił

KEY TERMS AND CONCEPTS

Kluczowe terminy i pojęcia

Moment of a Force: Scalar Formulation

torque on a flywheel: direction and size

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 by the moment arm.

The largest moment happens when the force acts tangentially to the flywheel. In that case, the force is perpendicular to the radius of the flywheel. The moment also gets larger when the applied force is larger or when the moment arm is longer.

The right-hand rule gives the direction of the moment. If the fingers of the right hand curl in the direction of the rotation, the thumb points along the moment direction. By convention, counterclockwise motion is positive, and clockwise motion is negative. This helps in analyzing machines and structures and in predicting how mechanical systems behave.

Torque on a Flywheel: Direction and Size

moment of a force: scalar formulation

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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key terms and concepts

Learn how torque, or moment of a force, depends on force size, moment arm length, and direction using a flywheel example and the right-hand rule.

Torque on a Flywheel: Direction and Size | 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.

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Torque on a Flywheel: Direction and Size

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