8.02x - Lect 4 - Electrostatic Potential, Electric Energy, Equipotential Surfaces
Why Physics Stack Exchange recommends it
Physics Stack Exchange users link it as the source when asking about or explaining electric potential, equipotential surfaces and the work done by an external agent.
Recommended by 2 people across 2 different months, 2016 to 2024.
What it is
Walter Lewin's MIT 8.02 lecture on electrostatic potential and electric potential energy. It covers the electron volt, conservative fields, equipotential surfaces and conductors as equipotentials, with live demonstrations. The format is a classroom lecture at the blackboard.
What people said
Recommends Rajdeep Sindhu · 2020-06 · Physics Stack Exchange · on “How is the magnitude of force exerted by the external agent equal to the electrostatic force when talking about electric potential energy?”
I was watching a video about Electrostatic Potential and Electric Potential Energy by Professor Walter Lewin [this video] when I encountered a question. So, Professor Lewin assumes that a charge $Q$ was placed in free space, and hence, no work was done to place it there. Then, another charge (a test charge) $q$ was placed at a distance of $R$ from $Q$ . Now, some work would have to be done by the external agent placing $q$ near $Q$ . We say that the charge was brought from a distance of $\infty$ from $Q$ to a distance of $R$ from it. The work that would be done by the external agent to do so would be equal to the potential energy possessed by $q$ at a distance of $R$ from $Q$ . So, we just need t
Recommends physicopath · 2024-11 · Physics Stack Exchange · on “Why is electric potential due to a positive point charge positive?”
Walter Lewin explains right in the beginning of the lecture how to calculate the electric potential of a point particle. I suggest that you watch the video and find your mistake. [this video]
Cites emnha · 2016-12 · Physics Stack Exchange · on “Vector $d\vec{r}$ in calculating work”
Could anyone tell me what and where is the origin and vector dr that prof. Walter Lewin used to calculate work here [this video] ? With origin I mean the coordinate origin to define vector r and dr. Why vector dr is same for both Coulomb force and Walter Lewin force?
Cites Jonathan Ginsburg · 2017-08 · Physics Stack Exchange · on “Why is it that any conductor is an equipotential?”
According to Prof. Lewin's lecture [this video] the metals (I extrapolate to conductors) are equipotentials; why is this? I can understand that the Electric Field all along the metal is zero, but not the equipotential.
Cites Joel Rodriguez · 2020-05 · Physics Stack Exchange · on “Confusion In Concept of Equipotential Surface”
I have recently come across this topic of equipotential surfaces. I have a very basic doubt: Q.) Let's say we are talking about a point P inside the equipotential surface(eg:sphere). Now, before considering the equipotential surface let's beforehand calculate the potential at point P. After calculating, condsider the equipotential surface. And potential on surface = potential inside surface (in walter lewins video). So ofcourse now the potential which we calculated before wouldn't be the same after drawing equipotential surface. So, how did the potential inside change by just drawing a surface ? Walter Lewins video [this video] , [16:25 - 16:55], he clearly says that potential on surface is same
Cites StefanH · 2021-12 · Physics Stack Exchange · on “The current flow in a neon light tube aligned with a static electric field”
If you put a neon light tube inside an electric field such that it is aligned with the field lines, it will start to emit light. This is caused by a current starting to flow inside the tube. This current are moving electrons. But I am wondering, should there not be a point when all free moving electrons have moved to one side? And when this "equilibrium" is reached, no light should be emitted anymore. But that is obviously not the case? But why? This is demonstrated in these lectures [this video] .