Chapter 2 Static Electricity BY MRS HORVATH Background

Chapter 2 Static Electricity BY MRS. HORVATH

Background Knowledge What sometimes happens when you comb your clean, dry hair?

Electric Charges All matter is made up of tiny particles. Particles carry units of electric charges. ELECTRIC CHARGES = units of electricity 3 types of electric charges: - positive (+) - negative (-) - neutral has same number of + and - charges

Moving Charges Only negative (-) charges can move from one neutral object to another. ELECTRICAL ENERGY = energy from charged particles Since negative (-) charges move, electric charges build up on objects. Some objects are positively (+) charged and others are negatively (-) charged.

So, what is static electricity? STATIC ELECTRICITY = a build up of electric charges. Objects with a build up of like charges repel. Objects with a build up of opposite charges attract.

Static Cling Clothes in a dryer rub together as the dryer turns. Negative charges move from one piece of clothing to another. Clothes become charged with static electricity (build up of negative charges). Your wool socks (+ charged) Your cotton shirt (- charged)

Attracting Neutral Objects Rubbing a balloon with wool may cause it to stick to a wall. The rubbed balloon has extra negative charges that repel the negative charges in the wall.

Shock, Spark, Crackle Cause rubbing shoes against the rug Effect pick up negative charges from rug Effect charges move or “JUMP” to another object Effect spark or crackle may occur

Lightning Positive charges build up at the top of a cloud. Negative charges build up at the bottom of a cloud. Negative charges in the cloud repel the negative charges in the ground. The ground becomes positively charge. The negative charges in the cloud jump to the ground.