1.Mouths are quiet.2.Begin the quick review section of

your notes.3.Raise your hand if you need

something.

1. Balanced chemical equation for respiration

2. Device that turns mechanical energy into electrical energy = Generator

Quick Review

C6H12O6+ 6O2 →6H2O +6CO2

3. Sources of mechanical energy = falling water, steam, wind

a. Steam can be produced using nuclear fission, burning coal, and sunlight.

4. Mechanical energy captured by a turbine5. A wire coil attached to the turbine’s shaft spins inside of a magnet = causes electrons to move = electricity.

Quick Review

1. Which of these does NOT use a turbine and generator to produce electricity?

A. Hydroelectric damB. Wind turbineC. Photovoltaic panelD. Nuclear reactor

2. Which of these describes how a nuclear reaction turns a generator, producing electricity?

A. Falling water turns a turbine.B. Water is heated, boils and the

steam turns a turbine.C. Wind is produced turning a

turbine.D. Nuclear explosions occur that

turn the turbine.

3. Which of these is NOT a way that steam can be produced to turn a turbine?

A. Water falling through a dam.

B. Chain nuclear reactionC. Burning coalD. Concentrated sunlight

4. Which of these explains how a turbine produces electricity in a generator?

A. The turbine has a magnet wrapped around it. When the magnet is turned inside of another magnet, electricity flows.

B. The turbine has a wire coil wrapped around it. When the coil is turned between the poles of a magnet, electricity flows.

C. The turbine has a wire coil wrapped around it. When the coil is turned inside of another wire coil, electricity flows.

D. The turbine has an insulator wrapped around it. When the insulator is turned inside of a conductor, electricity flows.

5. A nuclear power plant is broken and no electricity is flowing. As an engineer you have been called in to diagnose the problem. The turbine blades are in place and the generator produces electricity when the coil is turned by hand. Which of these is a possible explanation for the problem?A. The coil of wire is missing inside of the

generator.B. The turbine is malfunctioning and will not turn.C. The nuclear chain reaction has stopped

producing heat.D. The generator’s magnet is missing so it will not

produce electricity.

Lesson 3.4 – The Power Grid

Energy

1. Two different types of electricity = current (AC) and current (DC).

alternating

direct

I can explain the power grid and give pathway that electricity takes from a power plant to a home appliance. (2d)

a. Alternating current = produced by power plants and used in homes for lights, appliances, and outlets, electrons reverse direction

times per second.

I can explain the power grid and give pathway that electricity takes from a power plant to a home appliance. (2d)

60

2. AC power leaves the power plant but must be prepared to travel over long distances by a step-up transformer at a transmission substation.

I can explain the power grid and give pathway that electricity takes from a power plant to a home appliance. (2d)

a. A transformer changes the voltage of electricity. Voltage is how hard the electrons are pushed through a wire.

I can explain the power grid and give pathway that electricity takes from a power plant to a home appliance. (2d)

b. The voltage must be increased from the thousands of volts produced by the generator to 500,000 volts so it can be pushed over long distances.

1,000s volts

~500,000 volts

I can explain the power grid and give pathway that electricity takes from a power plant to a home appliance. (2d)

3. The electricity travels on high-voltage transmission lines, huge metal towers that carry electricity

I can explain the power grid and give pathway that electricity takes from a power plant to a home appliance. (2d)

4. Once the electricity reaches a town, the voltage must be decreased for use in houses using a step-down transformer at a power substation.

~7,000 volts

~500,000 volts

I can explain the power grid and give pathway that electricity takes from a power plant to a home appliance. (2d)

5. The power is then sent into a set of power lines that run through the town called the distribution network.

I can explain the power grid and give pathway that electricity takes from a power plant to a home appliance. (2d)

6. Once the power reaches a house, its voltage is further decreased with another step-down transformer before it enters the house at 120V.

120 volts

~7,000 volts

I can explain the power grid and give pathway that electricity takes from a power plant to a home appliance. (2d)

7. This entire system is called the power grid.

I can explain the power grid and give pathway that electricity takes from a power plant to a home appliance. (2d)

WORK WITH US…NOT AHEAD OF US!

Guided Practice

You are going to act like the electrons in the power grid. The card you will be given tells where you are now. You have to go to the next step in power grid!

Next stop…

Still acting like the electrons in the power grid! The card you will be given tells you a voltage. You have to go to the place in the power grid where you

would have that voltage.

Where am I?

Guided Practice1. The power is out in Shaw and as an engineer you have been called in to diagnose the problem. Power is leaving the power plant and has reached the transmission substation but is not reaching the transmission lines. Which part of the power grid is malfunctioning?

The high voltage transmission lines because this is how electricity flows from a transmission substation to a power substation.

I-N-D-E-P-E-N-D-E-N-T PRACTICEDo you know what that means?Label a sheet of paper, to be turned in: Your nameScienceDecember 18, 2012Power Grid IP

1. Key Point #1: What are the two different types of electricity?

2. Key Point #1: What is the difference between alternating current and direct current?

3. Key Point #1: Describe how the electrons in alternating current change each second.

4. Key Point #2: After electrons are made to move through wires with a generator, how are they prepared for their travel to customers?

5. Key Point #3: What is used to send electricity from a power plant over hundreds of miles to customers?

(5 Questions)

Exit Ticket

1. Which of these describes alternating current?

A. Produced by a battery; changes direction 60 times per second.

B. Produced by a battery; constantly flowing.

C. Produced by a power plant; changes direction 60 times per second.

D. Produced by a power plant; constantly flowing.

2. Which of these describes how electricity moves from a power plant to town?

A. High voltage electricity around 5,000 volts travels on high-voltage transmission lines.

B. High voltage electricity around 500,000 volts travels on high-voltage transmission lines.

C. High voltage electricity around 500,000,000 volts travels on high-voltage transmission lines.

D. High voltage electricity around 50 volts travels on high-voltage transmission lines.

3. What is the role of a step-up transformer and where is it found?

A. Increase voltage; transmission substation at a power plant

B. Increase voltage; power substation in a neighborhood

C. Increase voltage; transmission substation in a neighborhood

D. Decrease voltage; power substation in a neighborhood

4. Which of these explains the path of electricity after it has reached a town?

A. Step-up transformer at a power substation distribution network step-up transformer house

B. Step-up transformer at a power substation distribution network step-up transformer house

C. Step-down transformer at a power substation distribution network step-down transformer house

D. Step-down transformer at a power substation distribution network house

5. The lights are out. Power is reaching the transmission substation and the power substation. Which of these must have failed?

A. A Step-up transformerB. The power plantC. The distribution networkD. High-voltage transmission lines