Question

A huge (essentially infinite) horizontal nonconducting sheet 10.0 cm thick has charge uniformly spread over both faces. The upper face carries +95.0 nC/m2 while the lower face carries -25.0 nC/ m2. What is the magnitude of the electric field at a point within the sheet 2.00 cm below the upper face? (ε0 = 8.85 × 10-12 C2/N ∙ m2)

Answer 1

Answer:

$E = 6.77 *10^{3} N/C$

Explanation:

THE GIVEN sheet can be taken as two horizontal force  with surface charge density is

at one surface is ∈_1 = $95*10^ {-9} C/mm2$

at oher surface is ∈_2= $-25*10^{-9} C/mm2$

the magnitude of electric field due to surface charge is given as$\frac{∈}{2∈_O}$

So, electric field at P (2 CM below from surface is) = E_1 +E_2

$E = \frac{∈_1}{2∈_O} +\frac{∈_2}{2∈_O}$

$E = \frac{95*10^{-9} +25*10^{-9}}{2*8.85*10^{-12}}$

$E = 6.77 *10^{3} N/C$