electrostatics - Electric potential $V = kq/r$ derivation - Physics ...
2020年2月19日 · Your working isn't that clear. The potential is the negative of the work done by the field to bring $1C$ from a point of zero reference (usually set at infinity) to the specified position.
electrostatics - The difference between $V=kQ/r$ and $V=ED
2021年7月18日 · Tour Start here for a quick overview of the site
Calculating Charge created by Van De Graff Generator
2019年5月8日 · So I have a few questions regarding a Van De Graff Generator. With the Equation: V=kQ/r where V is the Voltage Potential, k is the constant, Q is the charge in coulombs and r is the radius of the sphere. 1.) Do I have to use a sphere? Can I use, say a cylinder that is metal? 2.) How does the Charge concept work?
Electric field and electric potential for spherical shell
2020年7月28日 · The formula V = kQ/R gives the potential at the surface of a spherically symmetrical charge, Q, of radius, R (on the surface of your shell). It is found by integrating the, E, field in from infinity. As you point out, the, E, inside the shell is zero, so the potential does not change as you go in from the surface.
electrostatics - Can a positive charge have a negative potential ...
2024年5月8日 · V=Kq/r for a positive point charge. Assume B is the closest distance of approach for any test charge without experiencing a force due to the positive point charge. Now, if I want to move the point charge further towards point A, wouldn't I be performing negative work, and hence the point would have negative potential?
electrostatics - Why many times $E= - {\rm grad} V$ does not give ...
2024年8月15日 · $$ V= \frac{1}{r}$$ $$-\nabla V = \frac{1}{r^2} \hat r$$ Which is the correct field direction for all valid points in space You need to use the correct field and not zhat, employing the spherical gradient
Why does the electric field strength for a dipole go as $1/r^3$?
2018年3月8日 · I've been given the following graphic to help wrap my head around this. If the potential can be shown to represent a $1/r^2$ relation, then I'm more than happy to accept that the electric field is...
Why does electric potential does not change along a wire ...
2022年1月6日 · The formula for potential V=kq/r doesn't count resistance to be a factor affecting it $\endgroup$
What is the electric potential inside a point charge?
2019年4月14日 · When dimensions become very small, we are no longer in the realm of classical physics where potentials have mathematical singularities as in the classical 1/r Coulomb potential.
When do we use the formula $E=kQ/r^2$? - Physics Stack Exchange
2021年5月3日 · The actual solution of this question is to be solved using Gauss' Law. However, I solved for charge inside (Q) using the formula E=kQ/r^2, putting E=+100 N/C and r=+0.1 m but the value doesn't match. Can someone guide me as to why my approach is wrong? Why can't we use the formula E=kQ/r^2?