Electric Charges and Fields

• Atoms contain charged particles known as electrons and protons.
• Electrons repel electrons, protons repel protons, and protons attract electrons.
• Protons and electrons have opposite electric charges; a proton has a positive (+) charge, while an electron has a negative (-) charge.
• Like charges repel each other, while opposite charges attract.
• The interaction between electric charges is called electricity.
• The force between charged objects is called electric force.

Electric Fields

• An electric field is a region around a charged object where its electric force is exerted on other charged objects.
• Electric fields and forces weaken with distance from the charge.
• Field lines represent electric fields, illustrating the force exerted on a positive charge at any point.
• Field lines point away from positive charges and toward negative charges.
• Single charges have straight field lines.
• Multiple charges create combined forces and more complex field lines.

Static Electricity

• Most objects are neutral, with an equal number of electrons and protons.
• Objects become charged by gaining or losing electrons.
• Losing electrons results in an overall positive charge.
• Gaining electrons results in an overall negative charge.
• Static electricity is the buildup of charges on an object without continuous flow.
• Charges are neither created nor destroyed due to the law of conservation of charge.
• If an object loses electrons, another object must gain them.
• Charges redistribute through friction, conduction, induction, and polarization.

Charging Methods

• Charging by friction involves the transfer of electrons between two uncharged objects when rubbed together.
• The object gaining electrons becomes negatively charged, while the object losing electrons becomes positively charged.
• Charging by conduction involves electron transfer through direct contact between objects.
• Electrons move from the object with more negative charge to the object with more positive charge.