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Electricity. The origin, motion, and energy of electrons in circuits; The role of batteries as energy sources and resistors as energy dissipaters in circuits; Conceptual understanding of potential difference (i.e., voltage); Current and resistance and the relationship between them.
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The origin, motion, and energy of electrons in circuits; • The role of batteries as energy sources and resistors as energy dissipaters in circuits; • Conceptual understanding of potential difference (i.e., voltage); • Current and resistance and the relationship between them.
In Chemistry, you already learned about the interaction of charges. • Objects with opposite charges (one negative, one positive) will attract each other. • Objects with like charges (both negative or both positive) will repel each other.
A particle with a positive charge is called a/an _______________. proton neutron electron
A particle with a negative charge is called a/an _______________. proton neutron electron
_________ means to push away. _________ means to pull together. charge charge attract attract repel repel
If an electrically-neutral object GAINS electrons, what charge does it now have? positive neutral negative
If an electrically-neutral object LOSES electrons, what charge does it now have? positive neutral negative
Let’s start with some vocab… Electricity Circuit Current
Let’s start with some vocab… Electricity- a form of energy resulting from charged particles. Circuit- a closed loop that electrons can flow through Current-a measure of the flow of electrons (how many electrons pass a point per second) (measured in Amps)
Click on a term to reveal its definition. circuit opencircuit closed circuit Proceed to quiz
Circuit: A closed-loop path of conduction through which an electric current flows
Open circuit: An incomplete path that will not permit an electric current to flow
Closed circuit: A complete path for electric current
Quiz: What type of circuit is shown in each of the following examples? Open circuit Closed circuit
Open circuit Closed circuit
Closed circuit Open circuit
Open circuit Closed circuit
Open circuit Closed circuit
Click on a term to reveal its definition and examples. Insulator Conductor Continue
Insulator: a substance through which electricity cannot flow readily Examples… wood plastic rubber sulfur glass
Conductor: a material through which electrons can move easily Examples… brass aluminum copper graphite water
There are two main types of circuits: Parallel Series and
Parallel circuits are circuits with more than one pathway through which electrons can flow. Series circuits are circuits with only one pathway through which electrons can flow.
What type of circuits are shown in the following examples? series parallel
parallel series
parallel series
Holiday lights parallel series
Types of energy sources: • Battery: • Has two TERMINALS: • One positively charged & one negatively charged • Chemical reaction occurs in the battery that separates the charges to the positive and negative sides
Electric Potential Energy • This separation of charges (from the chemical reaction) causes a build up of potential energy. • Electrons flow from an area of high PE to low PE. • Just like gravitational potential energy… video
Battery cont • When a circuit is created , electrons flow from the negative end to the positive end • electrons are repulsed by the negative side and attracted to the positive side
Electrical Energy can be transferred • This separation of charges (from the chemical reaction) causes a build up of potential energy. • Electrons flow from an area of high PE to low PE. • Just like gravitational potential energy… video
After the reading “what is voltage?” • Voltage is like water pressure • Voltage is like a “force” at which the current will flow
Potential Difference (voltage) • Voltage is the measure of potential energy supplied to each coulomb of charge • Units- volts (V) • Is dependent on the energy source NOT the circuit! • the more volts a source has, the more potential energy it has.
The rate (“speed”) at which electrons flow • Unit- ampere (A) • (aka “amps”) • An amp is one coulomb of charge per second Current
An amp is one coulomb of charge per second • A coulomb is the unit for charge • There are about 6.24x 1018 electrons in one coulomb
Resistance • Opposes the rate of flow of charge • Unit- Ohms ()
How are resistance and current related? - Lab and worksheet