The internal electric charge outside excitation refers to the photoelectric effect. This is only related with the metal itself, and is irrelevant to the outside, when the irradiation of metal mesh (if the material is zinc) the frequency of light to reach the minimum required when the excitation frequency, excitation control automatically, so people cannot stop ~ ~Do not know if I can help you ~ if you do not understand the interpretation of the question
Towards the opposite direction of electric field oriented mobile E, induced electric field induced charge resulting in the additional 0 and the external electric field E on the contrary, E 0 block in the conductor of the directional movement of free electrons. As long as the E>E 0, the electron will still move directionally until E=E 0, free of charge in the conductor will stop the directional movement; at E=E 0, and in the opposite direction, which means that the electric field is zero, no charge directional movement, which reached a state of static equilibrium. But it is worth noting that electrostatic balance stopped just macro directional movement, the charge inside the conductor is still in the thermal motion of irregular, but only charge distribution in the electrostatic equilibrium conductor surface as such, the surface potential and electric field intensity is stable to zero.
The metal net can shield the external electric field because of the electrostatic equilibrium phenomenon, which can make the inner part of the metal net not affected by the external electric fieldThe formation principle of electrostatic equilibrium: whether the conductor is charged, once it is in the external electric field, under the action of the external electric field E, the free electrons in the conductor is affected by the electric field force,
