Charge of a uniform density (8.0 nc/m2) is distributed over the entire xy plane. a charge of uniform density (3.0 nc/m2) is distributed over the parallel plane defined by z = 2.0 m. determine the magnitude of the electric field for any point with z = 3.0 m.

The electric field generated by an infinite plane uniformly charged is

where  is the charge density of the plane, while  is the vacuum permittivity.

Let's calculate the electric field of the first (xy) plane:


And now the electric field due to the second (z=2.0 m) plane:


The electric field of the two planes does not depend on the distance. Also, the charges on the two planes have same sign, so at z=3.0 m (and at every point with z>2.0m) the two fields point into the same direction and the total electric field is simply the sum of the two fields:

Try c ? that’s what i got

Ithink the answer would be 1,350!