THURSDAY DO NOW What is electricity? Why is it important for you to learn about electricity?

Today’s PLAN –1.1 Describe properties of electric and magnetic (electromagnetic) forces as being attractive or repulsive. –1.2 Explain how electric and magnetic force size depends on magnitudes of the charges, currents, or magnetic strengths involved and on the distance between the objects. –1.3 Differentiate between charges, current, electrical field, and magnetic field. Todays DO –We will complete the Magnetism Explore Activity. (4 th period only) –We will complete guided notes over Electricity. –We will get graded papers/quizzes back and talk about our grades and how to make up work.

FRIDAY DO NOW Begin completing your Analyzing Data Mid-Year Learning Check. (You will have about minutes to finish this quiz.) Do not write on the quiz. Answer the questions on your scantron. Do your own work. Do your best. When finished, turn over your scantron and make a list of the questions you felt confident about and the ones you were unsure about. For those you are unsure about, tell what specifically confused you.

Today’s PLAN –1.1 Describe properties of electric and magnetic (electromagnetic) forces as being attractive or repulsive. –1.2 Explain how electric and magnetic force size depends on magnitudes of the charges, currents, or magnetic strengths involved and on the distance between the objects. –1.3 Differentiate between charges, current, electrical field, and magnetic field. Todays DO –We will complete our Analyzing Data Mid-Year Learning Check –We will complete guided notes over Electricity and Circuits. –We will complete a foldable about Electric circuits to use next week during a lab.

Electricity

All matter is made up of ______________. The two types of sub- atomic particles that have a charge are _______________ and ______________. Protons - _____ charge Electrons - _____ charge Thinking back… electrons protons

Electricity comes from the movement or placement of these charged particles.

Think about a magnet… What happens when you try to touch the two north ends together? – They repel each other What happens when you try to touch the two south ends together? – They repel each other What happens when you try to touch the north and south ends together? – They attract each other

The same applies to ELECTRIC CHARGES Charges that are the same, repel each other. Charges that are different, attract each other. Two ProtonsTwo ElectronsProton & Electron

What’s going to happen?

The charges of protons and electrons cause the object they make up to be positively or negatively charged

Most objects normally have no overall charge. –This is because each atom has an equal number of protons and electrons.

However, an object can become charged by gaining or losing electrons. When an object loses electrons, it will have a _____________ charge. When an object gains electrons, it will have a _____________ charge

That’s Static Electricity! The build-up of electric charges Static means “not moving” or “not changing” –In static electricity, charges build up on an object, but they do not flow continuously.

Mini- Lab Number your group members 1-4. Student 1: Blow up and tie off a balloon. Then tie a string around the balloon’s knot. Student 2: Blow up another balloon and tie it off. Student 3: Hold the end of the string allowing the balloon to dangle. Student 4: Rub the balloon without the string on your hair. (This gives the balloon a negative charge – electrons move from your hair to the balloon) Student 1: Rub the balloon with the string on your hair. Student 4: Slowly move your balloon toward the hanging balloon. What happens? Student 2: Rub the hanging balloon with a dryer sheet. What does this do to the balloon’s charge? Student 1: Rub the balloon with the string on your hair. Student 4: Slowly move your balloon toward the hanging balloon. What happens?

How can an object become charged? Three ways to move electrons from one object to another: – Friction - rubbing – Conduction - touch – Induction – movement of electrons within an object

Often, a static discharge produces a spark. Static Discharge When a negatively charged object and a positively charged object are brought together, electrons transfer until both objects have the same charge. Static discharge is the loss of static electricity as electric charges transfer from one object to another.

Lightning is another example of static discharge.

Conductors Conductors allow electricity to pass through them easily. Example: metals (such as those inside of wires- copper)

Insulators Insulators do not allow electricity to pass through easily. Example: plastic, rubber (such as that on the outside of a wire)

Circuits A circuit is a pathway along which an electric current can travel to a device. There are two different types of circuits: 1.Series 2.Parallel

Series Circuit A series circuit has only ONE pathway for electricity to flow. All devices are located along this single pathway. Any break in the circuit (such as a open switch) will stop the flow of electricity and the device(s) will no longer work. Example: old type of Christmas tree lights.

Series Circuit Light bulb symbolBattery symbolSwitch symbol

Parallel Circuit A parallel circuit has MULTIPLE paths along which electricity can travel. If one pathway is broken, the others can still carry electricity. Example: household circuits, newer Christmas tree lights

Parallel Circuit

Series and Parallel Circuits

Electromagnets An electromagnet is a temporary magnet made by passing an electric current through a wire coiled around a metal core (such as an iron nail). Electromagnets have two advantages over normal magnets: 1.They can be turned on and off. 2.Their strength can be changed based upon the amount of current flowing through it.

Electromagnets The amount of current flowing through an electromagnet can be changed by: 1.Changing the number of batteries used (more batteries = stronger electromagnet) 2.Changing the number of wire coils (more coils = stronger electromagnet)

Electromagnets