Circuits

• What is electricity and how can you transfer it through circuits?

• What are the differences between parallel and series circuits?

• What are the advantages and disadvantages of using serial and parallel circuits?

- Electric Current

Flow of Electric Charges• Electric current is the continuous flow of

electric charges through a material. Measured in amps.

Review Questions

An electric current either transfers charges well or not very well.

1. What is something called that transfers energy well? (Ex. Metals)

2. What is something called that does NOT transfer energy well? (Ex. Non-metals)

Electric Charges

• A conductor transfers electric charge well.

• Metals are good conductors. Silver, copper, aluminum, and iron are metals.

• An insulator does not transfer electric charges well.

• Rubber, glass, plastic, and wood are good insulators. The rubber coating on an electric cord is an insulator.

- Electric Current

Electric Circuit

• An electric circuit is a complete, unbroken path through which electric charges can flow.

- Electric Circuits

Parts of a Circuit

Parts of a circuit

Energy sourceResistorWiresSwitchLoad

Comprehension Check

1. What is a circuit?

2. What is an example of a circuit?

- Electric Circuits

Series Circuits• In a series circuit, there is only one path for

the current to take.

- Electric Circuits

Parallel Circuits• In a parallel circuit, there are several paths for

the current to take.

Series and Parallel Circuits Activity

• Click the Active Art button to open a browser window and access Active Art

about series and parallel circuits.

- Electric Circuits

Complex Circuit

• a circuit that has more than one parallel or series circuit linked together

Comprehension Check

1. What is an electrical circuit?

2. What are the 3 types of circuits?

- Electric PowerElectric Power• The rate at which energy is transformed from

one form to another is known as power. Power is measured in watts (W).

Voltage• Voltage causes a current in an electric circuit.• Voltage is the difference in electrical potential

energy between two places in a circuit. The unit of measure of voltage is the volt (V).

• The energy that makes charges flow through a circuit is called electrical potential energy.

• An electric circuit needs a source of energy to have voltage. Voltage sources: a battery, a generator

Calculating Power

A household light bulb has about 0.5 amps of current in it. Since the standard household voltage is 120 volts, what is the power for this bulb?

• What are you trying to calculate?The power of the light bulb = ?

• What is the formula?Power = Voltage X Current

• Calculate.Power = 120 V X 0.5 APower = 60 W

- Electric Power

Question Answer

Comprehension Check

What is electric power?

Electric power is the rate at which electrical energy is transformed into another form of energy.

- Electric Power

Electrical Equipment and Fires

– The percentage of fires caused by a certain type of electrical equipment

Reading Graphs:

– What determines the size of each wedge in the graph?

- Electrical Safety

Electrical Equipment and Fires

– 15%

Reading Graphs:

– What percentage of fires are caused by appliances?

Electrical Equipment and Fires

– Cooking equipment is responsible for the most fires. Heating and cooling equipment is responsible for the fewest fires.

Interpreting Data:

– Which category of equipment is responsible for the most fires? Which category is responsible for the fewest fires?

- Electrical Safety

Summary

• Identify pictures of circuits as parallel or series.

Thursday Warm Up Compare and contrast series circuits and

parallel circuits in a Venn diagram. Series Circuit Parallel Circuit

Only one path for current to take

Unbroken path that has a current

Several paths for current to take

- Electric Circuits