Static Electricity Static Electricity A buildup of electric

Static Electricity

Static Electricity A buildup of electric charge on an object. Does not flow through wires “Static” means “not moving”. May “jump” from one object to another.

Matter is made up of tiny particles called atoms. Atoms contain tinier particles called electrons. Electrons can move from atom to atom and object to object. The number of electrons on the surface of an object can make the object have a negative or positive charge.

If the surface has more than the usual number of electrons, the object has a negative charge (-) If the surface has fewer than the usual number of electrons, the object has a positive charge (+).

How does a negative charge build up on an object? Electrons move to it from another object. How does an object get a positive charge? Electrons move from it to another object.

Electric Force: Is a push or pull between charged objects Objects have like charges repel, or push away from each other. Objects that have unlike charges attract, or pull toward each other. Can act between objects that do not touch each other.

Charging an Object When two objects rub against each other, some electrons may move from the surface of one to the other. The object that gains electrons will then have a negative charge. The object that loses electrons will then have a positive charge.

Ex. Rub a balloon on a wool sweater, electrons move from the surface of a sweater to the surface of the balloon. A negative charge builds up on the surface of the balloon. At the same time, a positive charge buildings up on the surface of the sweater.

Objects can become charged without touching each other. Ex. Move a balloon with a negative charge toward a wall that has no charge. The surface of the wall has an equal number of negative and positive charges. As the balloon nears the wall, the balloon’s negative charges repel the negative charges on the wall’s surface. The negative charges on the wall’s surface move away, toward the other side of the wall. This leaves behind extra positive charges on the wall’s surface. The surface of the wall near the balloon becomes positively charged http: //phet. colorado. edu/sims/html/balloons-and-static-electricity/latest/balloons-and-staticelectricity_en. html

This diagram shows what happens if you touch a balloon to the wall. The balloon sticks to the wall because opposite charges attract.

Sometimes an electric charge can jump from one object to another. Walking across the carpet in a pair of slippers. Electrons move from the carpet to the slippers and then to your body. Your body becomes negatively charged.

Touch a metal doorknob. The negative charge on your hand pushes away electrons on the surface of the doorknob. The surface of the doorknob then has a positive charge. Electrons may jump from your hand to the doorknob. You feel a mild shock or tingling. You may also see a spark of light. This is called an electric discharge.

Example of electric discharge Lightning: a negative charge builds up in a cloud. At the same time, the ground or another cloud becomes more positively charged. The streak of light you see in the sky is the electric charge that jumps between two clouds, or between a cloud and the ground.

• Bill Nye The Science Guy - Static Electricity

Vocabulary – Words to Know 1. 2. 3. 4. Static electricity- a buildup of electric charge on an object. electron- a very tiny particle with a negative charge. Electric force- a push or pull between charged objects. Electric discharge- the quick movement of electric charge from one object to another

Discussion Question A charged balloon attracts small bits of paper. Why does this happen