Electrical charge

4.1 Simple phenomena of magnetism

4.3 Electrical quantities

Electrical charge

  1. Static electricity

    1. Electrostatic charges can be produced via the friction of rubbing two materials together1
    2. These charges can be detected using a gold leaf electroscope: the metal plate and gold leaf are both charged in the same way as the charge being detected so repel each other, causing the gold leaf to rise

  2. Charge

    1. There are positive and negative charges
    2. Charge is measured in coulombs
    3. Like charges repel and opposite charges attract

  3. Electric field

    1. An electric field is a region in which an electric charge experiences a force towards the opposite charge
    2. Electric field lines point from positive to negative (magnetic field lines point from north to south)

  4. Conductors and insulators

    1. Electrical conductors conduct charge since they have free electrons and electrical insulators do not since the electrons are bound firmly to their atoms
    2. Charge can be induced by bringing a charged material towards one of two touching electric conductors: the charge will separate with the opposite charge being attracted towards the material and the same charge repelled from it; separating the two objects preserves the inbalance of charge in them
  1. This is known as the Triboelectric effect ↩