Electricity Electric Charge and Static Electricity Electric Charge

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Electricity Electric Charge and Static Electricity

Electric Charge R Charged parts of atom R Protons: positive charge R Electrons: negative charge R Atom Visualization R R Positive charges repel each other Negative charges repel each other Charges that are different attract each other Electricity: the interaction between electric charges

Electric Force R The attraction or repulsion between electric charges R Electric Field R Invisible region around a charged object where the object’s electric force is exerted on other charged objects R If another object is placed in the way it will either be pushed away or pulled toward that charged object R Single Charges R The greater the distance, the weaker the electric field R The closer the field lines, the stronger the electric field R Electric Force Field Visualization

Multiple Charges R The electric field will be altered when there is more than one object R The electric fields of each individual charge combine by repelling or attracting

Static Electricity R Typically, atoms are neutral because they contain an equal number of protons and electrons R Some objects can become charged R Protons are bound tightly in the center of an atom but electrons can leave their atoms R If an object loses electrons, it has an overall positive charge R If an object gains electrons, it has an overall negative charge R The buildup of charges on an object is called static electricity R In static electricity, charges build up on objects but they do not flow continuously

Transferring Charges The Law of Conservation of Charge: charges are neither created nor destroyed. If one object gives up electrons, another object gains those electrons. R Charging by Friction R Charging by Conduction R Charging by Induction

Charging by Friction ROccurs when two objects rub together RObject that gains electrons becomes negatively charged RObject that loses electrons becomes positively charged

Charging by Conduction R Occurs when two objects touch R Electrons transfer from the object that has the more negative charge to the object that has the more positive charge R This means that a positively charged object will gain electrons when it touches an uncharged object

Charging by Induction R Objects do not touch when charges transfer R The movement of electrons to one part of an object that is caused by the electric field of a second object R The electric field around the charged object attracts or repels electrons in the second object

Static Discharge R Electrons have a tendency to move, returning the object to its neutral condition R Static discharge is the loss of static electricity as electric charges transfer from one object to another R This means that when a negatively charged object and a positively charged object are brought together, electrons transfer until both objects have the same charge

Static Discharge R Will often produce a spark R When electrons transfer objects, they heat the air around the path they travel until it glows R The glowing air is the spark you see R Interactive Example: Static Electriciy & Discharge R Lightning - huge spark of static discharge R Occurs to restore a neutral condition in the clouds R Electrons move from areas of negative charge to areas of positive charge R Will reach Earth when negative charges at the bottom of the storm clouds cause the surface of the Earth to become positively charged by induction R Electrons will jump between the cloud and Earth’s surface, which occurs through conduction

Links & Clips RMythbusters Part 1 RMythbusters Part 2 RBrainpop! Static Electricity

Section 1 Vocabulary R Electric force R Electric field R Static electricity R Conservation of charge R Friction R Conduction R Induction R Static discharge