CIE IGCSE Physics

Revision Notes

4.2.3 Electrons

Charge & Electrons

  • Electrons are negatively charged particles
  • Usually the number of electrons around an atom is equal to the number of (positive) protons in the nucleus of the atom, and hence the atom is neutral

 

atom-proton-neutron-electron, IGCSE & GCSE Physics revision notesThe number of negative electrons in an atom balances the number of positive protons

 

  • If, however, and object gains extra electrons, it will gain an overall negative charge
  • If it loses some of its electrons it will be left with a positive charge
    • Negative charges are the result of gaining electrons
    • Positive charges are the result of losing electrons

 

Exam Question: Electrons

Electrons & Conduction

  • A conductor is a material that allows charge to flow through it
  • An insulator is a material that does not allow the flow of charge through it

The table below lists some common conductors and insulators:

Conductors and insulators table (1), IGCSE & GCSE Physics revision notes

Author: Jenna

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