Static Electricity Mod

Static Electricity

Electric Charges What is an Atom made of? Answer  Protons, Neutrons, & Electrons There are two types of Electric Charges: 1 – Positive (Protons) 2 – Negative (Electrons)

Atoms contain an equal number of Protons and Neutrons; Positive & Negative cancel each other out.

What is Static Electricity? Static electricity is the accumulation of excess (extra) electric charges on an object. Ex. Atoms in shoes hold electrons more tightly than atoms in carpet.

Shoes and Carpet

Conservation of Charge Charge is never created nor destroyed; Electrons simply move from one object to another. Ex. When shoes rub on carpet, electrons transfer from the carpet to the shoes.  

Shoes  more electrons (negative charge) Carpet  less electrons (positive charge)

Opposites Attract “Opposite” charges attract “Like” charges repel

Conductors & Insulators An excess of electrons can move easily through materials conductors. Ex. Skin is a good conductor. Electrons from your shoes repel each other and transfer to your skin.

Metal conductors: 

Atoms in metals have electrons that easily move through materials.

Ex. Copper; great for electric wires, because Copper is a good conductor of electricity.

Insulators Insulators are materials that don’t allow electrons to move easily through them. **Electrons are held strongly to atoms in insulating materials.** Examples of insulators include: 

Plastic, Wood, Rubber, & Glass.

Ways that Objects can be Charged

Induction Friction Conduction

Charging by Induction Induction: Objects can be charged by bringing a charged object near a neutral object.  The two objects don’t touch  If a charged object is brought near a neutral object the charged object will attract unlike charges in the neutral object and repel like charges in the neutral object.  After an object is charged by induction it will have the opposite charge of the charging object and will attract it.

Ex. Balloon with (-) charge approaches sleeve with (-) charge. The negative electrons on the sleeve move away from the balloon, leaving (+) charges in its place. (+) and (-) attract, causing the balloon to stick to the sleeve.

Charging by Friction Friction: 

If you rub one against another, sometimes electrons leave one object and stick to another leaving both objects charged.

Charging by Conduction Conduction: 

Electrons can be transferred from one object to another by touching. When a charged object touches another object some charge will transfer to the other object. It is always the electrons that move in solid objects. Objects charged by conduction will have the same charge as the object charging it and therefore repel it.