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Find the electric field at a distance along the axis from a disc of radius and uniform charge density?

User Ihammys
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Final answer:

The electric field at a distance z above the center of a disk with radius R and uniform charge density σ is calculated by integrating the contributions from infinitesimal rings of charge, resulting in the formula E = σ / (2ε0) * (1 - z / (√(z^2 + R^2))).

Step-by-step explanation:

Finding the Electric Field of a Circular Disk

To find the electric field at a distance z above the center of a disk with radius R and a uniform charge density σ, we can integrate the contributions to the electric field from each infinitesimal charge element on the disk. The formula to calculate the electric field of a disk is given by:

E = σ / (2ε0) * (1 - z / (√(z^2 + R^2)))

where σ is the surface charge density (in coulombs per square meter), ε0 is the permittivity of free space (8.854 x 10-12 C²/(N·m²)), z is the distance from the disk along the axis through the center of the disk, and R is the radius of the disk.

The approach involves breaking down the disk into rings of charge and then integrating these rings from 0 to R to find the net electric field. Each ring contributes to the field at a point z above the disk, and by superposition, we can add these contributions to find the total field.

User Carlo Mendoza
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