Warm Up #10 Which particles in an atom have electric charges? Where are electrons in an atom?

Lesson 1: Electric Charge and electric forces Ch. 9 Electricity Lesson 1: Electric Charge and electric forces

Essential Questions How do electrically charged objects interact? How can objects become electrically charged? What is an electric discharge?

How can you bend water? ACTIVITY Inflate a balloon and tie the end. Place an X on one side of the balloon. Hold a funnel over a large bowl and pour a cup of water through the funnel. As the water flows gently, bring the balloon as close to the stream without getting it wet. What do you notice? Rub the X side of the balloon on a sweater. Repeat step above with the X side facing the stream of water. Why did this happen? What do you think would happen if I just touched my sweater instead of rubbing it?

Electric Charges All matter is made of particles called atoms All atoms are made of smaller particles – protons, neutrons, and electrons Protons = positive, inside nucleus Neutrons = neutral, inside nucleus Electrons = Negative, around nucleus Worksheet on parts of atom

Electric Charges How can objects become electrically charged?

Electric Charges Electrically neutral atoms – have same amount of protons and electrons Electrically positive atoms – have more protons than electrons Electrically negative atoms – have more electrons than protons Electrically charged atoms are called ions Static charge – an unbalanced negative or positive electric charge on an object Electrical Charge Worksheet

Electric Forces Electric field – area surrounding a charged object Electric force – the electric field applies a force to other charged objects The strength of the electric force between 2 charged objects depends on the total amount of the charge on both objects and the distance between the objects Attract/Repel Worksheet

Warm Up #11 What is 1 material through which electrons can move easily? How does an electric insulator differ from an electric conductor?

How can a balloon push or pull? activity Inflate 2 balloons and attach a 10 cam length of string to each balloon. Hold balloons by the string and slowly bring together. What did you observe? Hold 1 balloon over some packing peanuts. Rub each balloon against a piece of wool cloth. Repeat Step 2. Rub 1 balloon with wool. Repeat Step 3.

Transferring electrons Electric insulator – a material in which electrons can’t easily move Ex. Glass, rubber, wood, air Electric conductor – a material in which electrons can easily move Ex. Metals (copper, aluminum)

Transferring electrons When objects made of different materials touch, electrons tend to collect on the object that holds electrons more tightly – transferring charge by contact Transferring charge by induction – a process by which one object causes 2 other objects that are conductors to become charged without touching Polarized – when electrons concentrate at 1 end of an object Static Electricity Worksheet BrainPOP – Static Electricy

Transferring electrons Transferring charge by conduction – conducting objects with unequal charges touch, electrons flow from the object with a greater concentration of negative charge to the one with a lower concentration, which continues until the concentration on charge of both is equal I.E. water flowing from a container with a higher water level to one with a lower level until both are equal

Warm up #12 Why is grounding important?

Electric Discharge Electric discharge – the process of an unbalanced electric charge becoming balanced Can occur slowly when hair loses negative charge when being brushed Can occur quickly when a flash of lightning occurs Grounding – providing a path for electric charges to flow safely into the ground Very important when dealing with lightning