ELECTRICALLY SPEAKING: "MORE POWER TO YOU"

ELECTRICALLY SPEAKING: "MORE POWER TO YOU"

MASTER TEACHER Pamela R. Parks

GRADES 5 - 8

OVERVIEW
This lesson provides students with an understanding of the concept of electrical energy. During the lesson the students will model the movement of electrons along a wire to form an electrical current, label a concept map of hydroelectric production, and build two types of electrical circuits. These projects incorporate activities that utilize the multiple intelligences for brain compatible learning. Technology and hands-on activities have been planned to enhance the integration of the multiple intelligences that activities alone prove lacking. As students investigate the concept of electrical energy, they understand and relate its impact on their own lives.

ITV SERIES
3-2-1 Classroom Contact: "More Power to You: Generating Electricity"

LEARNING OBJECTIVES
The students will be able to:
*explain electricity
*describe and demonstrate an electrical current
*diagram the production of a steady flow of electricity by a generator
*calculate electrical power and cost
*construct a parallel circuit and a series circuit
*compare a parallel circuit and a series circuit

MATERIALS
(per class)
overhead projector
screen
Transparency: "Concept Map"
Transparency: "Formulas"
Timer
40 - 4 cm styrofoam balls
1 plastic see-through container that will hold all the balls (marked: battery)
(per group)
4 D cell batteries
6 flashlight bulbs and holders
8 pieces of bell wire (20 gauge, single strand) 10 - 15 cm in length
4 pieces of bell wire (20 gauge, single strand) 20 - 30 cm in length
2 rolls of masking tape
(per student)
Calculator
Colored markers (washable)
pencil
Activity Sheet #1
Activity Sheet #2
Activity Sheet #3

VOCABULARY
electricity                        turbine
amperes                          generator
volts                               series circuit
watts                              parallel circuit

PREVIEWING ACTIVITIES
Say, "An electrical current is electrons flowing through a wire in order to light bulbs, run televisions, and power computers. To visualize how this happens I need 10 volunteers." Say, "Would you please stand in a row at the front of the room. These people represent atoms in a wire. Since atoms are always moving let me see you atoms wiggle a little while you keep your place in the wire. Let's pretend this is a battery. (Hold up a container with styrofoam balls.) Inside the battery are atoms with billions of electrons. (Toss a few of the styrofoam balls into the air.) Each of you atoms have electrons. (Give each atom in the wire a styrofoam ball.) Batteries have two ends, or terminals. If you connect a wire to one terminal of the battery, extra electrons will flow into the wire, like this: (Start handing balls, one at a time, to the person at the end of the line. Tell the atoms to pass the "electrons" on. The atom at the end will end up with too many electrons and start to drop them.) As you can see, the electrons cannot keep moving through the wire when it is filled up. To keep the electrons moving smoothly through the wire, we must connect the other end of wire to the other terminal of the battery. (Arrange the line of students in a circle.) Hand the electrons to the atom next to you, and pass the electrons around the circle and return then to the battery." Say, "Now I will increase the electric current or amperes which is the number of electrons that move through a wire in a given time. To double the current or double the amperes in this wire I will hand out two electrons at a time. Ready? (Hand out two balls at a time as fast as you and the atoms can handle them. ) Did you feel yourselves getting warmer as I increased the current? The force that moves the electrons through the wire is measured in volts. When the current increases, a real wire will heat up too. The force that moves the electrons through the wire is measured in volts. That's the way electric stoves, hair dryers, and CD players work." Thank the volunteers and ask them to be seated. At this time set up teams (groups) of 4 in the class and pair the students within each team. (Team #1 - 2 A's and 2 B's)

FOCUS FOR VIEWING
To give students a specific responsibility while viewing say, "Can you teach someone how an electric current is produced or made? Watch this video segment and see if you can." (An electrical current is make by passing a magnet over a metal wire or by passing a metal wire over a magnet. This will produce a current that is alternating or that stops and flows, stops and flows.)

Begin tape at the title image. Video is "More Power to you. Generating Electricity." Audio is "More Power to You." Pause tape. Video is girl with tired arms. Audio is, "What do you use to make the wires spin in the magnet? ...Lots of stuff." Say, "A's are to explain to B's how an electrical current is produced. A's talk for 30 seconds and B's only listen actively. Go!" Set timer: 30 seconds. At the end of 30 seconds say, "Stop! Now, the B's are to tell the A's the explanation in their own words of how electricity is made. B's, you can edit or correct the explanation, if you need to do so. Go!" Set timer: 20 seconds. After 20 seconds say, "Stop, please. Now, for 15 seconds explain the production of electricity to the team member across from you. # 1 explain to # 4, # 2 explain to # 3. Any corrections that may be needed are to be made at the end of the 15 seconds by the listening team member. Go!" Set timer: 15 seconds. At the end of 15 seconds say, "Stop, please." Hold up a hand, if necessary. In order to assess for understanding and to give immediate feedback, randomly, ask a student to explain to the whole class how electricity is make. (An electrical current is made by passing a magnet over a metal wire or by passing a metal wire over a magnet. This will produce a current that is alternating or that stops and flows, stops and flows.) Praise the student and the whole class. Pass out Activity Sheet #1 (Mind Map or Concept Map). Say, "Look at the words in the word list. (Pause for a few seconds in order to give the students time to read the words.) As you view the next video segment, number the words in the same sequence shown in the video." Resume the tape. Pause the tape. Video is, "the lighted light bulb." Audio is, " and that makes electricity." Rewind the tape.

Pause the tape. Video is, "diagram of flowing water." Audio is, "it uses water power to make electric power. As the tape is rewinding ask the teams to discuss this question, " What kind of power is converted to electrical power by Hoover Dam? How?" (Water power is changed or converted to electric power. Water is released at the base of the dam. The water flow turns a turbine that is connected to a shaft that turns a coil of wire inside a magnet that moves electrons over wires to produce electricity.) Say, " As you view the video segment one more time, check your numbering sequence." Resume the tape.

Pause the tape. Again, video is, "the lighted bulb." Audio is, "And that makes electricity." Have the students label the concept maps in Round Robin. # 1 identifies label for step 1, the circle at the bottom of the page (water flow). If all team members agree, then each team member labels that first step or circle, water flow, on his/her own "Mind Map." This procedure continues until all the steps or circles are labeled in Round Robin style. Allow 3 minutes for the completion of the task. Set timer: 3 minutes. Ask all the # 3's to stand and randomly ask for the steps in order as the others check their own "Mind Map" validity. (Sequence: water flow, turbine, shaft, coil of wire, magnet, electricity)
Ask the class to view the next video segment and listen for ways electricity is used in Las Vegas. (light, t.v.'s, radios, air conditioning) Resume the tape.

Pause the tape. Video is, "Hoover Dam." Audio is, "Water power from Hoover Dam, that's what. "Pass out Activity Sheet #2 (laminated) and the washable colored markers.   Say, " Now, let's calculate consumer cost of the electrical power.
Follow these steps to calculating electrical energy and cost:
     1. Determine power.
     2. Convert watts to kilowatts.
     3. Calculate kilowatt hours.
Let's circle the volts, amps, and hours in the first problem.   Circle the cost in the second problem. This could help you in substituting the values in the problem set up. You will have 10 minutes to complete the four problems. Show the problem set up and the substitution of the values. You may use the calculators for the actual calculations. Box in the answers. Remember that in science, no number stands alone." After 10 minutes ask all the #1's to record the set up, substitution of values, and the boxed answer for problem #1 on the back of the laminated page. (#2's do the same for problem 2, #3's for problem 3, and #4's for problem 4.) Say, #1, when you have completed the task, please, hold up your work." Ask one of the #1's to read the task to the class. Continue this method of assessing for understanding and feedback for the rest of the problems. (#2's show problem 2, etc.)

Resume the tape. Stop the tape. Video is, "young girl." Audio is, "...inside the magnet which generates electricity."

POST-VIEWING ACTIVITIES
Pass out Activity Sheet #3.(One per group) Say, "We are going to build two kinds of electrical circuits and compare the flow of electricity through the two different kinds of circuits. Team members #1 and #2 will build the series circuit. Team members #3 and #4 will build the parallel circuit. You will have 10 minutes to complete the tasks as a pair. When the team agrees on the conclusions, Team member #1 will then record the conclusions for the team. When all the light bulbs light up, give each other on the team a pat on the back. The materials you will need are in the baskets."

ACTION PLAN
Field trip to the USS Lexington or to a power production plant to tour and note the production of electricity and its uses.

Make a personal inventory of ones own uses of electrical power.

EXTENSIONS
LANGUAGE ARTS
Make journal entries describing the enrichment of life due to electricity.

MATH
Calculate the cost of the student electrical use for a 24-hour period.

ART
Create a collage of electrical uses that improve the student's daily life.

MUSIC/BAND
Write the lyrics to a favorite tune using "electrical" vocabulary.

COMPUTER SCIENCE
Create a multimedia presentation using Hyperstudio software highlighting the importance of electrical energy to today's technology.

ACTIVITY SHEET #1

POWER CONVERSION:

Write inside each circle one of the following word/s for the path of power conversion:

         coil of wire
         turbine
         magnet
         electricity
         water flow
         shaft

ACTIVITY SHEET #2

ELECTRICAL ENERGY COST:

Follow the steps of the procedure below to calculate the following problems.

1. Determine power (watts): P = V x l

P (watts) = V (voltage) x l (current or amperes)

2. Convert watts to kilowatts: kW =   P   (1 kilowatt = 1000 watts)
                                                          1000
                                          kW (kilowatts) = P(watts)
                                                                         1000

3. Calculate kWh (kilowatt hours): kWh = kW x h

kWh (kilowatt hours) = kW (kilowatts) x h (hours)

______________________________________________________

1. A microwave oven operates on 5 amps of current on a 110-volt circuit for one hour. Calculate the total kilowatt hours used.

2. How much would it cost to run the microwave in Problem 1 if the cost of energy is $0.10 per kWh?

3. A refrigerator operates on 15 amps of current on a 220-volt circuit for 18 hours per day. How many kilowatt hours are used per day?

4. If the electric costs are 15 cents per kWh, how much does it cost to run the refrigerator in Problem 3 per day?

ACTIVITY SHEET # 3

ELECTRIC CIRCUITS:

How does the flow of electricity in a series circuit differ from the flow of electricity in a parallel circuit?

1. Using the diagram below build a series circuit.

What happens when a bulb is removed?

Prediction

Results:

2. Using the diagram below build a parallel circuit.

What happens when a bulb is removed?

Prediction:

Results:

3. In which kind of circuit did the bulbs glow more brightly?

CONCLUSIONS:

Updated: April 01, 2008