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Chapter 6, Section 3. Series and Parallel Circuits: Lighten Up. HW: 6.3 PTG #1-9. LO Compare series and parallel circuits and learn the language of electricity. SC Compare series and parallel circuits Recognize generator output limit Modify the Electron-Shuffle model of electricity.
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Chapter 6, Section 3 Series and Parallel Circuits: Lighten Up
HW: 6.3 PTG #1-9 • LO • Compare series and parallel circuits and learn the language of electricity. • SC • Compare series and parallel circuits • Recognize generator output limit • Modify the Electron-Shuffle model of electricity • Do Now: • Copy LO and SC on new left side page • WDYS/WDYT pg. 614 • Agenda: • Do Now • Investigate Part A
Investigate Part A • Electron Shuffle • 3 bulbs in parallel • Coulombs go to • Light Bulb 1 if your bday is in Jan, Feb, Mar, Apr • Light Bulb 2 if your bday is in May, June, July, August • Light Bulb 3 if your bday is in Sept, Oct, Nov, Dec • 1-volt battery=1 Joule per Coulomb • Battery: “The battery Voltage is 1 Volt, which equals one joule of energy for each coulomb” • Coulomb: “One coulomb of energy receiving one joule of energy” • Light Bulb: “I just received 1 Joule of energy from that coulomb”
Students answer... • Pg. 615 • #4a, b
Investigate Part A • Electron Shuffle • 3 Volt battery • 1 Amp current
Investigate Part A • Electron Shuffle • 1 Volt battery • 2 Amp current
Students answer… • Pg. 616 • #7 a-e
HW: 6.3 PTG #1-9 • LO • Compare series and parallel circuits and learn the language of electricity. • SC • Compare series and parallel circuits • Recognize generator output limit • Modify the Electron-Shuffle model of electricity • Do Now: • What happened to the brightness of the bulbs in a parallel circuit when compared to the bulbs in series circuit? • Agenda: • Do Now • Investigate Part B
Investigate Part B • #1-2 complete in groups, discussion • #3-4 complete in groups, show teacher • #5-6 complete in groups, show teacher, discussion
Physics Talk • Series Circuit • Total voltage of the battery is divided equally between all bulbs in the circuit. • Coulombs of charge must go through each bulb and drop off joules of energy. • If one bulb is removed, the circuit is open and ALL the bulbs will go out. • 1 volt battery, each bulb will receive 1/3 • Bulbs will appear dimmer
Physics Talk • Parallel Circuit • Total voltage provided to each bulb is equal to the voltage of the battery. • Each bulb has a complete circuit from the battery to the bulb and back to the battery • If one bulb is removed, others will remain lit • Bulbs will be equally bright. • Battery will run out more quickly
Physics Talk • Series example: • 6 volt battery • How many joules will each bulb get? • Parallel Example • 6 volt battery • How many joules will each bulb get?
Physics Talk • What about the current in a parallel circuit? • Current (coulombs/sec) is divided in a parallel circuit • Example: If a parallel circuit has a 3 amp current, each bulb gets one amp of current • How much current would each bulb get if it was a 9 amp circuit?
Put it all together! • 9 Volt battery with a 3 amp current • Each bulb receives ____ joules of energy • Each bulb receives ____ amps of current
Put it all together! • 9 Volt battery with a 3 amp current • Each bulb receives __9__ joules of energy • Each bulb receives __1__ amps of current • One coulomb will pass each resistor (bulb) every second and drop 6 volts there.
Physics Talk • What is a resistor? • What is voltage drop? • A conductor that controls the current in a circuit. • How many joules the coulomb drops off at each resistor
The Language of Electricity • 2 kinds of electric charges • Positive (protons) • Negative (electrons) • Like charges (++ or - -) will repel • Protons and electrons have opposite but equal charges • Protons (1+) • Electrons (1-)
The language of electricity • Electrons move in circuits and carry the electrical current delivering energy to the bulb • Protons do not flow because they are locked within atoms • Standard “package” of electric charge is called a Coulomb (C)=6.25 x 1018 electrons • Approximately the charge of a bolt of lightning!
The language of electricity • Standard rate of flow through a circuit is an ampere (A). • # coulombs that pass through a point in one second
The language of electricity • Resistance is the opposition to the flow of electric charge • Resistors are objects that oppose flow of electric charge (light bulb) • Example: High resistance-Tungsten filaments in light bulbs glow as they “rob” energy from passing electrons, causes the tungsten to get hot and glow=LIGHT! • Example: Low resistance-copper wire, electrons transfer little energy so we use copper to conduct electricity in circuits • Measured in Ohms (Ω) • Was the steel wool high or low resistance? Why?
The language of electricity • Batteries or generators provide energy to the electrons (coulombs) • Energy given to each coulomb is measured in Volts (V)
Essential Questions pg. 620 • What does it mean? • How do you know? • Why should you care? • LO and SC reflection