- Consider a

**circular disc of radius ‘a’**which carries a

**uniform surface charge density ρ**, C /m

_{s}^{2}.

- Say the

**disk lies on x - y plane**(or z = 0 plane) with its axis along the z axis as shown in the figure.

- We need to find out

**electric potential (V)**due to a circular disk at a point

**P (0, 0, h) on the z axis (z > 0).**

- Electric potential (V) at a point due to any surface charge (ρ

_{s}) is given as:

- In this case,

**ds = ρ dρ dφ**

(Since it’s a disc, the varying terms are

**radius ρ and angle φ**)

**R = (ρ**

^{2}+ h^{2})^{1/2}- Hence

**electric potential (V)**is given as:

- On solving further the equation becomes

- As

**a → 0**, electric potential

**(V) also tends to zero i.e. V → 0.**

- Hence the

**electric potential at point (0, 0, h)**is given as:

**ALSO READ:**

**- Gauss's Law - Theory.**

**- Gauss's Law - Application To a Point charge.**

**- Gauss's Law - Application To An Infinite Line Charge.**

**- Gauss's Law - Application To An Infinite Sheet Charge.**

**- Gauss's Law - Application To a Uniformly Charged Sphere.**

**- Numericals / Solved Examples - Gauss's Law.**

**- Scalar Electric Potential / Electrostatic Potential (V).**

**- Relationship Between Electric Field Intensity (E) and Electrostatic Potential (V).**

**- Electric Potential Due To a Circular Disk.**

**- Electric Dipole.**

**- Numericals / Solved Examples - Electric Potential and Electric Dipole.**

**- Energy Density In Electrostatic Field / Work Done To Assemble Charges.**

**- Numericals / Solved Examples - Electrostatic Energy and Energy Density.**

**- Numericals / Solved Examples - Gauss's law...**

**Your suggestions and comments are welcome in this section. If you want to share something or if you have some stuff of your own, please do post them in the comments section.**

I'm looking for the answer to this when the point in question is not along the axial line. It's out there for a ring, but not for a disk.

ReplyDeleteI was just wondering. Since you used a definite integral, why do you have C? Doesn't it cancel out when you integrate it from 0 to a?

ReplyDelete