Electric Charge

• Ion

• Static Charge

• Electric Force

• Electric Field

• Insulator

• Conductor

• Electric Discharge

Vocabulary

• Atoms are made of:

  • Protons – positive charge

  • Neutrons – no charge (neutral)

  • Electrons – negative charge

• Nucleus – center of the atom, holds the protons and neutrons

• The electrons orbit around the nucleus

First, Let's Review The Atom!

In All Things, Balance

• In atoms, there are exactly as many protons (with a positive charge) as there are electrons (with a negative charge)

• Atoms are electrically neutral (they have no overall charge)

• However. . . some atoms can gain or lose electrons

  • What happens to their electric charge, then?

• Ion – an atom that is either positively or negatively charged

  • Positive ions form when atoms lose electrons

  • Negative ions form when atoms gain electrons

• The protons and neutrons never leave the nucleus to form ions

Ions

• Electrons aren’t “stuck” to one nucleus in a solid

• They can move from one nucleus to another

• Physical motion or contact can cause electrons to “jump” from one solid to another

Electrons In Solids

What Happens When Electrons Jump?

• A balloon is rubbed on your hair

  • The electrons in your hair are held more loosely than the electrons on the balloon

• Which way do the electrons jump?

  • What happens to the overall charge of your hair?

  • What happens to the overall charge of the balloon?

Static Charge

• Static Charge - an imbalance in the electric charge of an object

• Caused by the transfer of electrons from one object to another

• One object becomes positively charged, while the other becomes negatively charged