What is an electric charge? Describe the structure & charges in an atom. Charge- physical property Charged objects exert a force- push or pull- on other charged objects Law of electric charges- like charges repel, different charges attract
Electric Force & Field Electric force- force between charged particles Size depends on amount of charge & distance between charges Electric field- the region around a charged object in which an electric force is exerted on another charged object Objects in an electric field react to the electric force
How are objects charged? Do atoms have a charge? Friction- electrons are wiped from one object to another Examples? Conduction- electrons move from one object to another in direct contact Examples? Induction- charges in an uncharged metal object are rearranged w/o direct contact
Conservation & Detection Charges are not created or destroyed, only transferred Electroscope- glass flask w/metal rod in rubber stopper w/2 metal leaves attached.
Moving Charges Electrical conductors- charges move easily; ex. Metals Insulators- charges can not move easily, electrons do not flow freely; ex. Plastic, rubber, glass, wood, & air
Static electricity Electric charge at rest on an object Static-not moving Ex. Clothes in a dryer; tumbling causes transfer of charge due to friction; when friction stops, charges are static
Electric Discharge Loss of static electricity as charges move off an object May be slow or quick Ex. lightning