Name: stability in potential energy diagrams
Uploaded: 2023-04-30T10:57:45.000Z
Duration: 1 min 10 s
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K12 Standards

north-carolina-k-12-science-standard-course-of-study

North Carolina K-12 Science Standard Course of Study

9-12

Physics

Energy

PS.Phy.6.2

Energy Diagrams - II

Considérons un patineur patinant sur une rampe parabolique sans frottement, la force agissant sur le patineur est donnée par la pente négative de la courbe d’énergie potentielle. Au bas de la rampe, la force agissant sur le patineur est nulle.
Considérons un diagramme d’énergie potentielle imaginaire : la force résultante agissant sur le patineur sera nulle au point x1 et de même au point x2.
Tout déplacement loin du point x1 entraînera une force de rappel sur le patineur, dirigée vers le point x1.
Alors que tout déplacement du patineur au point x2 entraînera une force, dirigée loin du point x2.
Tout point minimum de la courbe d’énergie potentielle est un point d’équilibre stable, tandis que tout point maximum est un point d’équilibre instable.
Si l’énergie totale du patineur est E2, alors le patineur pourra s’échapper et aller au-delà du point x2. Mais si l’énergie totale est E1, alors le patineur sera coincé entre les positions x0 et x2.

diagrammes d'énergie - ii

Les diagrammes d'énergie sont importants pour comprendre la dynamique d'un système. La topologie d'un diagramme d'énergie aide à illustrer les points d'équilibre du système.
Le point du diagramme d'énergie où l'énergie potentielle du système est la plus basse est appelé le minimum local. Le système a tendance à rester dans cette position indéfiniment à moins d'être influencé par une force nette. La pente du diagramme d'énergie potentielle au niveau du minimum local est nulle, ce qui indique qu'il n'y a pas de force nette agissant sur le système. La pente est positive de chaque côté du minimum, ce qui suggère que la force nette agissant sur le système est une force de rappel. De même, la force nette agissant sur le système au niveau des maxima locaux est également nulle, mais il s'agit d'un point d'équilibre instable. Tout mouvement loin de ce point entraîne une force agissant à l'opposé du point.
Il y aura toujours un point d'équilibre neutre caractérisé par le régime constant de l'énergie potentielle du diagramme d'énergie, où la force nette sur le système sera nulle. Tout mouvement de chaque côté de la position d'équilibre neutre entraînera une force nette sur le système, ni de rappel ni de perturbation.

Ce texte est adapté de <a href="https://openstax.org/books/university-physics-volume-1/pages/8-4-potential-energy-diagrams-and-stability">Openstax, University Physics Volume 1, Section 8.4: Potential Energy Diagrams and Stability</a>.

Diagrammes d'énergie - II

Les diagrammes énergétiques sont importants pour comprendre la dynamique d’un système. La topologie d’un diagramme d’énergie permet d’illustrer les points d’équilibre du ...

Education

Enseignement

JoVE Core

Physique

Unit 1

Unité 1

Potential Energy and Energy Conservation

Énergie potentielle et conservation de l'énergie

KEY TERMS AND CONCEPTS

TERMES ET CONCEPTS CLÉS

stability in potential energy diagrams

Potential energy diagrams show how stable a system is at different positions. Their shape, or topology, helps identify equilibrium points. An equilibrium point is a place where the system can stay in balance because the net force is zero.

At a local minimum, the potential energy is lowest. The system tends to remain there unless a net force acts on it. The slope at the minimum is zero. The slope is positive on both sides, so the force acts as a restoring force and pushes the system back.

A local maximum is also an equilibrium point, but it is unstable. The net force at this point is zero. If the system moves away from the top, the force acts farther away from the point.

Potential energy diagrams can also show neutral equilibrium. In this case, the potential energy stays constant over a region, and the net force is zero. A small move to either side still creates a net force, but it is neither restoring nor disruptive.

Stability in Potential Energy Diagrams

gravitational potential energy

Gravitational Energy from Height and Weight

Gravitational potential energy depends on an object’s weight and its height above the ground. It is one part of the total potential energy of a system, which comes from the interactions between objects. In a system, the total potential energy is the sum of the potential energies for all the objects. Potential energy is usually grouped into two main categories: gravitational potential energy and elastic potential energy. Gravitational potential energy describes the energy tied to a body’s...

elastic potential energy

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Elastic potential energy is stored when an elastic object is deformed, such as when a spring is stretched. An object is elastic if it returns to its original shape and size after the force is removed. This stored energy is part of a system’s potential energy. An ideal spring also exerts an elastic force. The work done by this force can be described as a change in the spring’s elastic potential energy. For a perfectly elastic spring in one dimension, that work depends only on the spring...

conservation of mechanical energy

Mechanical Energy in Isolated Systems

Mechanical energy in an isolated system is the total of kinetic energy and potential energy. Kinetic energy is the energy of motion, and potential energy is stored energy. The transcript focuses on what happens when energy shifts within a system without outside influence. In this case, only conservative forces act on the objects in the system. Conservative forces can transfer energy between kinetic energy and potential energy. Friction and drag do not act here, and no external force from...

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non-conservative forces

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conservation of energy

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conservation of energy: application

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force and potential energy in one dimension

force-and-potential-energy-in-one-dimension

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force and potential energy in three dimensions

force-and-potential-energy-in-three-dimensions

Gradient Force from 3D Potential Energy

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energy diagrams - i

Potential Energy Diagrams and Stability

Potential energy diagrams help describe how a mechanical system moves. Because energy is a scalar quantity, the system’s behavior is easier to interpret from the diagram. A skater on a parabolic ramp is a clear example. The ramp height changes with horizontal position, so the potential energy changes as well. As the skater moves down from the highest point, potential energy changes into kinetic energy. Kinetic energy is the energy of motion. The net force on the skater is gravitational force,...

energy diagrams - ii

Potential energy diagrams show how stable a system is at different positions. Their shape, or topology, helps identify equilibrium points. An equilibrium point is a place where the system can stay in balance because the net force is zero. At a local minimum, the potential energy is lowest. The system tends to remain there unless a net force acts on it. The slope at the minimum is zero. The slope is positive on both sides, so the force acts as a restoring force and pushes the system back. A...

key terms and concepts

Explore how potential energy diagrams reveal stable, unstable, and neutral equilibrium points, including local minima, maxima, and zero net force.

Stability in Potential Energy Diagrams | JoVE K12

physics

JoVE Core Physique présente plusieurs branches de la physique fondamentale grâce à des vidéos animées concises et faciles à comprendre ; cela inclut: la cinématique, la dynamique, la mécanique des fluides, la mécanique statique, les ondes et l'acoustique. En parallèle, les vidéos de scientifiques à l'action démontrent l'application de concepts associés à ces domaines dans des expériences de recherche classiques et originales réalisées dans des laboratoires modernes du monde entier.

Pennsylvania State Academic Standards

Physical Science

3.2.9-12.S

Louisiana Student Standards for Science

High School

Chemistry

HS-PS3-4

HS-PS3-5

Tennessee Academic Standards

PHYS.PS3.3

PHYS.PS3.8

CHEM1.PS3.4

Virginia  Standards of Learning

HIgh School

PH.4

PH.4.b

Alabama Course of Study Science

9-12.PS.1.1

9-12.P.2.3.b

Next Generation Science Standards

HS-PS3-2

Texas Essential Knowledge and Skills

PHYS.7

PHYS.7.C

new-york-state-science-learning-standards

New York State Science Learning Standards

HS. Energy

HS-PS3-2.

The universe is composed of matter in different forms, and all forms of matter contain energy.&#160; The different forms of energy on Earth originate from ...

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Conservation of Energy

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PS.Phy.6.1

Work

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Positive, Negative, and Zero Work

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Work-energy Theorem

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Work and Energy for Variable Forces

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work-energy-theorem-for-motion-along-a-curve

Work-Energy Theorem for Motion Along a Curve

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Work Done Over an Inclined Plane

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Work Done by Gravity

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Power

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Understand the relationship among work, energy, and power.

Stability in Potential Energy Diagrams

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