(iii) A disk of radius 2.5 cm has a surface charge density of 5.3mu C/m^2 on its upper face. What is the magnitude of the electric field produced by the disk at a point on its central axis at distance z=12cm from the disk? (4 mks)

To find the magnitude of the electric field produced by the disk at a point on its central axis at a distance cm from the disk, we can use the formula for the electric field due to a uniformly charged disk: where:- is the electric field,- is the surface charge density,- is the permittivity of free space ( ),- is the distance from the disk along the central axis,- is the radius of the disk.Given:- ,- ,- .Substitute these values into the formula: Calculate the denominator: Calculate the term inside the parentheses: So, Now, substitute back into the equation: Therefore, the magnitude of the electric field produced by the disk at a point on its central axis at a distance cm from the disk is approximately .