Electricity and Magnetism
If a charge Q is affected by an electrostatic force, there is an electric field. If at some point the electric field is known, we can find the electrostatic force on a charge Q at that point
The matter is divided into molecules, which in turn are divided into atoms. These atoms are composed of two parts: nucleus and periphery.
If a body has more electrons than protons, it is negatively charged. If it has more protons than electrons it is positively charged
If an electric field is close to a metallic body, part of it is positively charged and other part negatively charged