Question

Two 3.31 cm by 3.31 cm plates that form a parallel-plate capacitor are charged to +/- 0.608 nC. What is the electric field strength inside the capacitor if the spacing between the plates is 1.832 mm?

Answer 1

In order to find the E-field, we need to use the formula

$E=\frac{\sigma}{\epsilon_0}$

where σ is the charge density on the plate and ε0 = 8.85x10^-12

To find the charge density, we just need to find the charge over area

Area = (3.31x10^-2)^2 = 0.00109 m^2

σ = C/A = .608x10^-9/0.00109 = 5.5494 x 10^-7

E = 62705.31 V/m