Why Can Tzz in Maxwell's Stress Tensor Be Non-Zero in Electrostatics?

[member 743765]

In summary Tzz in maxwells stress tensor represents a force per unit area in the z direction acting on an area element that is oriented along the z direction also why it could be non zero eventhough the electric field along z is zero and I'm talking here in electrostatic

 

[Orodruin]

It is not a force on a charge distribution. It is the force of the EM field on one side of the surface acting on the EM field on the other side.

 

[member 743765]

It is not a force on a charge distribution. It is the force of the EM field on one side of the surface acting on the EM field on the other side.

Can I use the analogy with a box when you apply forces on x and y directions on its sides but not on the top and bottom there will be pressure on the z direction on the top and bottom