Potential energy Definition and 1000 Threads

In physics, potential energy is the energy held by an object because of its position relative to other objects, stresses within itself, its electric charge, or other factors.Common types of potential energy include the gravitational potential energy of an object that depends on its mass and its distance from the center of mass of another object, the elastic potential energy of an extended spring, and the electric potential energy of an electric charge in an electric field. The unit for energy in the International System of Units (SI) is the joule, which has the symbol J.
The term potential energy was introduced by the 19th-century Scottish engineer and physicist William Rankine, although it has links to Greek philosopher Aristotle's concept of potentiality. Potential energy is associated with forces that act on a body in a way that the total work done by these forces on the body depends only on the initial and final positions of the body in space. These forces, that are called conservative forces, can be represented at every point in space by vectors expressed as gradients of a certain scalar function called potential.
Since the work of potential forces acting on a body that moves from a start to an end position is determined only by these two positions, and does not depend on the trajectory of the body, there is a function known as potential that can be evaluated at the two positions to determine this work.

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  1. S

    Doubts on Work-Energy theorem for a system

    While studying energy conservation on Morin I found this explanation about the work-energy theorem for a system. Using Koenig theorem $$\Delta K_\textrm{system}=\Delta K +\Delta K_\textrm{internal}$$ so we have I've got two main question on that: Why are only external forces considered for...
  2. S

    Partial derivative of potential energy and work

    For a conservative force \vec{F}=-\vec{\nabla} U \implies dW=-\vec{\nabla}U \cdot d\vec{s} Where d\vec{s} is the infinitesimal vector displacement. Does the following hold? -\frac{\partial U}{\partial \vec{s}}=-\vec{\nabla} U \cdot d\vec{s}=d W, i.e. the infinitesimal work is minus the...
  3. A

    Potential energy stored in a dipole

    1- Potential energy stored in a dipole placed in an electric field E is maximum when a- E is perpendicular to the dipole moment b- E is parallel to the dipole moment c- E is anti-parallel to the dipole moment
  4. L

    Time period in harmonic oscillation.

    Homework Statement Homework Equations Find Time Period. Find the error in my solution. The Attempt at a Solution Where i am wrong ?
  5. S

    Why do conservative forces try to reduce potential energy?

    I do not understand the reason why a conservative force always "tries" to reduce the potential energy of a system at its minimum (forgive me if I said it in a wrong way). The explanation I gave me is: since for a conservative force, from the definition of potential energy, W=-\Delta U that...
  6. S

    Simple gravitational potential energy

    Homework Statement A 400-N child is in a swing that is attached to a pair of ropes 2.00 m long. Find the gravitational potential energy of the child-Earth system relative to the child’s lowest position when (b) the ropes make a 30.0° angle with the vertical Homework Equations Ug=mgy The...
  7. R

    How Many 100W Bulbs Can Be Powered by Converting Water's Potential Energy?

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  8. Anthony Santelices

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  9. H

    Orbital stability and fictitious potential energy with a change of convention

    The condition for a stable orbit is given by (3.42), where ##V'## is the fictitious potential energy (potential energy of the corresponding fictitious one-dimensional problem) and ##r_0## is the radius of the circular orbit. The result ##n>-3## is obtained by using the convention that positive...
  10. i_hate_math

    A really confusing question on potential energy,

    Homework Statement A 975 g block is released from rest at height h0 above a vertical spring with spring constant k = 410 N/m and negligible mass. The block sticks to the spring and momentarily stops after compressing the spring 24.2 cm. How much work is done (a) by the block on the spring and...
  11. A

    Max speed and tension of bungee jump?

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  12. J

    Conservation of energy - elastic potential energy and k.e.

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  13. P

    Electric Potential Homework: Proton vs Alpha Particle

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  14. iamazombie911

    Gravitational Potential Energy

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  15. U

    Gravitational Potential Energy in orbit

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  16. R

    Potential energy and conservation of energy

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  17. R

    Particle potential energy - acceleration?

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  18. M

    Finding Force from Potential Energy Function

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  19. hackhard

    B How to check if force is conservative?

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  20. M

    Why can we add/subtract constants to potential function?

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  21. blee22

    Electrostatic, Electric Field,Electrostatic potential energy

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  22. Danny Boy

    I Why is reflection coefficient defined this way

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  23. F

    Electric Potential Energy Problem. Intuition needed

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  24. J

    Understanding Electric Potential Energy Calculations: Addressing Sign Confusion

    I am confused about the signs in calculating the potential energy change from the electrostatic force. Suppose there was a point charge +q1 and I moved a second point charge +q2 from a distance of b from q1 to a distance of c from q1. c is smaller than b. So the potential energy change is - ∫...
  25. S

    What Is the Minimum Energy Required to Break a Molecule Apart?

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  26. K

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  27. P

    Integrals and potential energy

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  28. N

    What is the gravitational potential energy of the box relative to the floor?

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  29. neilson18

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  30. K

    Circular Motion and Energy Calculations

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  31. T

    Does internal potential energy affects temperature?

    Hello If I take an extreme case, where a body has only an internal potential energy with zero internal kinetic energy, does this body have a temperature? Another question related to it: if two objects A and B having different temperature: A: having only internal potential energy and B having...
  32. A

    Find the interaction potential energy

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  33. FruitNinja

    Potential Energy function for this system

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  34. J

    Potential energy in solids,liquids and gases

    Homework Statement Is the potential energy between atoms in solids, liquids and gases, elastic or electrical? I've read in some sources that for solids, p.e. > k.e. because it has the strongest intermolecular forces among the three states of matter. So I'm assuming it is elastic potential...
  35. AntoineCompagnie

    Potential energy variation = work of -(conservative forces)

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  36. Rmehtany

    Gravitational Self Potential Energy

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  37. Liz Hoyt

    Can Calculating a Horse's Leg Spring Constant Predict Jump Heights?

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  38. Q

    Tannor Quantum Mechanics derivative of variance of position

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  39. gracy

    Potential energy in concentric shells

    Homework Statement There are two concentric shells of radii a and b respectively ,inner shell has charge Q and outer shell is neutral what will be potential energy of outer shell due to inner shell Homework Equations ##V##=##\frac{KQ}{R}## PE=Charge .V The Attempt at a Solution I know what...
  40. V

    Non-Zero Potential Energy in SHM: Is Spring Stretched in Mean Position?

    in shm,if minimum potential energy of an shm is not zero,does that mean that in mean position ,spring is stretched. eg mass attached to a vertical spring.
  41. Buzz Bloom

    Question regarding GR wrt potential energy

    The motivation for this post comes from a discussion on another thread https://www.physicsforums.com/threads/questions-regarding-mass-volume-x-density.851172/ It seems worthwhile to me to try a simplification in this post to hopefully avoid the complications raised in the cited thread. Assume...
  42. Gian Lukmana

    Gravitational potential energy of a cylinder to a particle

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  43. Physicscookie

    What is the change in potential energy of two blocks in a physics problem?

    I present the following problem to my AP and have received a variety of answers, being a new physics teacher I am not sure that my answer is correct. I would love to see the solution and justification. Thanks One attempt based on the inference that one block is gaining U (A) and the...
  44. T

    Can potential energy be greater than total energy?

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  45. lucphysics

    Kinetic and potential energy (satellite low orbit)

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  46. B

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  47. S

    LaTeX Potential Energy Stored in latex rubber

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  48. B

    Solving for potential energy after time t.

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  49. E

    Potential Energy of an Electron in a Battery

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  50. R

    At what angle does the normal force go to zero?

    Homework Statement An ice cube is placed on top of an overturned spherical bowl of radius r, as indicated in the figure. If the ice cube slides downward from rest at the top of the bowl, at what angle θdoes it separate from the bowl? In other words, at what angle does the normal force between...
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