How Is the Potential Inside a Charged Sphere Constant?

In summary, the potential inside a sphere is constant due to the fact that the electric field inside the sphere is zero, which results in zero work being done on a charge inside the sphere. This can be explained using Coulomb's law and knowledge of charge in an electric field, without using Gauss's law or the partial derivative for rate of change in potential. The potential is shown to be constant inside the sphere on graphs depicting an inverse-distance relationship, with a maximum value at the surface of the sphere and a constant value across one side of the sphere passing through the center. This concept is further explained by Professor Walter Lewin in his lectures on YouTube.
  • #1
svar
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can someone explain how the potential inside a sphere is constant, in terms of using coulomb's law and knowledge of charge in an electric field, without directly invoking gauss's law or the partial derivative for rate of change in potential.

the graphs depicting potential around a sphere show (symmetrical) inverse-distance relationship rising to a maximum value of potental at the surface of the sphere, then the line flattens to show constant value right across one side of sphere to the other passing through the centre of sphere. my question is how to explain the value of potential is constant inside the sphere.
 
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  • #2
svar said:
can someone explain how the potential inside a sphere is constant,
it's not. the potential inside any arbitrary sphere is not constant. can you further specify the properties of this sphere for that we know what you are trying to say?

in terms of using coulomb's law and knowledge of charge in an electric field, without directly invoking gauss's law or the partial derivative for rate of change in potential.

the graphs depicting potential around a sphere show (symmetrical) inverse-distance relationship rising to a maximum value of potental at the surface of the sphere, then the line flattens to show constant value right across one side of sphere to the other passing through the centre of sphere. my question is how to explain the value of potential is constant inside the sphere.
 
  • #3
thanks folks, problem solved, thanks to prof. walter lewin of MIT on his utube lectures.

If E inside the sphere is zero, then F on a charge in the sphere is zero, therefore W done on the charge is zero as it moves about in the sphere, delta V is therefore zero, and V = the the value at the surface.
 

FAQ: How Is the Potential Inside a Charged Sphere Constant?

What is the equation for calculating the electric potential inside a charged sphere?

The equation for calculating the electric potential inside a charged sphere is V = kQ/r, where V is the electric potential, k is Coulomb's constant (9x10^9 Nm^2/C^2), Q is the charge of the sphere, and r is the distance from the center of the sphere to the point of interest.

How does the electric potential change as you move closer to the center of the charged sphere?

The electric potential decreases as you move closer to the center of the charged sphere. This is because the distance from the center decreases, resulting in a smaller value for r in the equation V = kQ/r. As a result, the electric potential becomes more positive as you move away from the center of the sphere.

Is the electric potential inside a charged sphere always positive?

No, the electric potential inside a charged sphere can be positive or negative depending on the charge of the sphere and the distance from the center. If the charge is positive, the electric potential will be positive. If the charge is negative, the electric potential will be negative. Additionally, the electric potential can change from positive to negative as you move from the center of the sphere to the surface.

How does the electric potential inside a charged sphere compare to that of a point charge?

The electric potential inside a charged sphere is similar to that of a point charge at the same distance from the center. However, as you move towards the center of the sphere, the electric potential decreases more rapidly than that of a point charge. This is because the charge is spread out over a larger area in a sphere, resulting in a weaker electric field and a faster decrease in potential.

Can the electric potential inside a charged sphere ever be zero?

Yes, the electric potential inside a charged sphere can be zero at the center of the sphere. This is because the distance from the center is zero, resulting in a value of r=0 in the equation V = kQ/r. As a result, the electric potential becomes zero at this point. However, the electric potential cannot be zero at any other point inside the sphere.

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