Hamilton’s principle maximises potential energy?

In summary, Hamilton's principle seeks to minimize the difference between kinetic energy and potential energy, with a fixed kinetic energy. This results in the maximization of potential energy. When the limit of kinetic energy approaching zero is considered, the Lagrangian becomes solely the negative of potential energy. This is explained by Feynman in his lectures, particularly in Figure 19-6. However, considering this limit may not be meaningful in understanding the overall concept of maximizing potential energy.
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sentai
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Hamilton’s principle minimises kinetic energy minus potential energy, that is, with a fixed kinetic energy, Hamilton's principle maximises potential energy. What if we consider the limit that the kinetic energy or the mass/the inertia can be ignored then the lagrangian is solely the negative of potential energy. How to understand the potential energy needs to be maximised?
 
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  • #3
anuttarasammyak said:
Feynmann does a good explanation around Fig 19.3 in https://www.feynmanlectures.caltech.edu/II_19.html.
Thank you, however, I don't think he said anything about maximization of PE and its meaning?
 
  • #4
Sorry, Fig 19-6 and its around explains it.
 
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  • #5
anuttarasammyak said:
Sorry, Fig 19-6 and its around explains it.
Thanks for pointing it out. Then how should we understand the limit of KE->0, then min(L)=-max(PE)?
 
  • #6
As Feynman stated we are looking for the path KE-PE integral on which should be extreme.
KE=0 takes place at the top of trajectory in Fig 19-6 but I do not think considering such "limit of KE->0" is meaningful.
 

1. What is Hamilton's principle?

Hamilton's principle is a fundamental concept in classical mechanics that states that the motion of a system can be described by minimizing the action, which is the integral of the Lagrangian over time. It is also known as the principle of least action.

2. How does Hamilton's principle relate to potential energy?

Hamilton's principle states that the motion of a system is described by minimizing the action, which is the integral of the Lagrangian over time. The Lagrangian is a function that combines the kinetic and potential energies of a system, and minimizing the action means that the potential energy is maximized.

3. Why is potential energy maximized in Hamilton's principle?

In Hamilton's principle, the potential energy is maximized because it is combined with the kinetic energy in the Lagrangian. By minimizing the action, the system's motion is described in a way that conserves energy, and maximizing the potential energy is a way to achieve this conservation.

4. What is the significance of Hamilton's principle in physics?

Hamilton's principle is a fundamental concept in classical mechanics that is used to describe the motion of systems. It is a powerful tool for understanding the behavior of physical systems and is used in many areas of physics, including mechanics, electromagnetism, and quantum mechanics.

5. Are there any real-world applications of Hamilton's principle?

Yes, there are many real-world applications of Hamilton's principle. It is used in the design of mechanical systems, such as bridges and buildings, to ensure that they are stable and energy-efficient. It is also used in the study of fluid dynamics, where it is used to describe the motion of fluids and optimize their flow. Additionally, Hamilton's principle is applied in the field of optics to design lenses and mirrors for optimal light refraction and reflection.

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