Electricity objectives Static The word static means stationary

Electricity objectives

Static • The word “static” means stationary or not moving. • When an object becomes charged by a rubbing process (friction), it is said to possess a static charge.

Static Electricity • Refers to electric charges that can be collected and held in one place. • It is the temporary transfer of electrons.

Bill Nye: Static Electricity

Charges on Objects…. . Remember: • 1. Protons have a positive charge • 2. Electrons have a negative charge

• 3. When the number of protons equals the number of electrons, the atom is neutral.

Neutral Atom

• When an atom or material becomes charged, it is because electrons transfer into or out of the atom or material. • Static Electricity: Snap, Crackle, Jump | Science | Classroom Resources | PBS Learning. Media

Insulator • A material that does not allow electric charges to move easily. • Examples: Glass, plastics, wood, rubber, etc

Conductor • Is a material in which electric charges can move more easily. • Example: metals

• Since static electricity is charge that is held fixed in one place, only insulators can retain a static charge. • Conductors such as copper and aluminum allow charge to flow.

Insulator – Conductor Video Clips • https: //www. youtube. com/watch? v=Zg. DIX 2 G Oax. Q (watch first 7 mins) • https: //www. youtube. com/watch? v=3 kynt. Gq T 14 s • https: //www. youtube. com/watch? v=q. Uhxm. X Zw. Pmg

Changing the Charge of an Atom • The movement, or transfer of electrons from one atom to another changes the charge on the atom. • When an atom loses electrons, the atom becomes positively charged. • When an atom gains electrons, the atom becomes negatively charged.

• If electrons are removed from a neutral object, the object will become positively charged. • If electrons are added to a neutral object, the object will become negatively charged

How can a positively or negatively charged object become neutral?

Activity 7 -1 B Visualizing Charge Transfer Pg. 231

Text Questions • Page 237 # 1 -19 • Electroscope Demo Video Clip (Question # 12)

Electric Discharge • The removal of electric charge from an object. • • Ex. Lightening “shocks”

Video Clip: Charging and Discharging • https: //www. youtube. com/watch? v=cr. Omf 6 z 1 M 40

The Coulomb (C) • • The unit of electric charge. • • It takes the addition or removal of 6. 25 x 1018 electrons to produce 1 C of charge.

Laws of Electric Charges: • 1. Like charges repel • 2. Unlike charges attract • 3. Charged objects attract some neutral ones.

Balloon Example • When you rub a balloon in your hair, the balloon becomes negatively charged. • Since the balloon is an insulator, the negative charge remains in a nearly fixed location on the balloon. • If you place the charged balloon against the wall, the negative charges in the wall are repelled away from the balloon. • The part of the wall closest to the balloon now has a positive charge • The negative charge on the balloon will be attracted to the positive wall and therefore the balloon will stick

• Static Electricity and Water - You. Tube

Technologies and Static Electricity • Lightning Rods

• A lightening rod is a conductor that is placed on top of a building. If lightening occurs near the building, the large amount of charge will pass through the lightening rod to the ground rather than the building. • Allowing charge to flow into Earth’s surface is called Grounding.

Photocopier (Page 241)

Electrostatic air cleaner

• The ionizers remove electrons from particles in the air, and the charged particles are then attracted to a plate on the device.

Text Questions Page 246 -247 Chapter 7 Review • Page 246 #1, 3, 6, 11, 12, 14 • Page 247 #15, 16, 18, 19, 21, 25, 26