Electric Field Energy (dielectrics

[da_warped_1]

Im having some problems with this question

Some cells in the human body have a layer of negative charge on the inner surface and a layer of positive charge of equal magnitude on the outer surface. The charge densities are +/- 5.0e-4 C.m^-2, the cell wall is 5nm thick and the cell wall material has a dielectric constant of K = 5.4

Given that the cell is approx spherical which a radius of 3 micrometres, estimate the total electric field energy stored in the wall of the cell...


any help would be much appreciated, thanks...

 

[member 553083]

The total electric field energy stored in the wall of the cell can be calculated using the equation for electric field energy density, given by U= 1/2*ε*E^2. In this case, the electric field energy density is given by U = 1/2 * 5.4 * (5e-4)^2. Multiplying this by the surface area of the cell (which is given by 4πr^2), we get a total electric field energy stored in the wall of the cell of 3.73e-15 Joules.