Electrical Charge and Static Electricity Things that go ZAP!!!!!!!!

Electric Charge Electrical energy is the energy associated with electric charges An electric charge is a property that causes subatomic particles such as protons and electrons to attract or repel each other Protons have a positive charge (+) Electrons have a negative charge (-)

Electric Charge When an atom gains an electron it is negatively charged When an atom loses an electron it is positively charged A net electric charge is produced when there is too many or too few electrons

Coulomb The SI unit for electric charge is the coulomb It takes 6.24 x 1018 electrons to make 1 coulomb A lightning bolt is 10 to 20 coulombs A flash camera uses about 0.025 coulombs to produce a flash

Electric Forces Like charges repel each other where opposite charges attract Electric force is the force of attraction or repulsion between electrically charged objects If you double the electric charge of an object you double the electric force If you double the distance between two objects the electric force is one-fourth as strong

Electric Fields The electric field is the effect an electric charge has on other charges in the space around it The strength of an electric field depends on the amount of charge that produces the field and the distance from the charge

Static Electricity and Charging Static electricity includes how charge is transferred between objects Law of conservation of charge states that the total charge in an isolated system is constant Charge can be transferred by friction, conduction and induction

Friction An example of charging by friction is rubbing a balloon against your hair The electrons will move from your hair to the balloon The balloon now has a negative charge and your hair has a positive charge

Conduction A Van de Graff generator ( a charged metal sphere) will cause a charge by contact There is a reduction in the charge of the Van de Graff generator because some has gone to the person’s hair Your hair will stand on end due to the charge

Induction When you go to touch a metal doorknob after walking across a carpet is induction Your hand has a negative charge from walking across the carpet The electrons in your hand repel the electrons in the doorknob Induction is a transfer of charge between materials without contact

Static Discharge Static discharge occurs when a pathway through which charges can move forms suddenly When you go to touch the doorknob the air between your finger and the knob is charged This allows electrons to flow from your hand to the doorknob