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ElectricityElectricity
Can you get a light bulb to Can you get a light bulb to light?light?
Using the equipment given to you, try to find as Using the equipment given to you, try to find as many ways as possible to get the light bulb to light.many ways as possible to get the light bulb to light.
Diagram four ways in which you were able to get Diagram four ways in which you were able to get the light bulb to light. Label the battery, the wire, the light bulb to light. Label the battery, the wire, and the bulb.and the bulb.
Diagram at least three ways in which you were not Diagram at least three ways in which you were not able to get the bulb to light.able to get the bulb to light.
Questions:Questions:
1. From your observations, what conditions seem to 1. From your observations, what conditions seem to be necessary in order for the bulb to light?be necessary in order for the bulb to light?
Successful AttemptsSuccessful Attempts
Producing Electric CurrentProducing Electric Current The flow of charged particles is an electric current.The flow of charged particles is an electric current. Charges flow from a conductor with a higher potential Charges flow from a conductor with a higher potential
difference through a wire to a conductor with a lower difference through a wire to a conductor with a lower potential difference.potential difference.
Conventional current is defined as positive charges flowing Conventional current is defined as positive charges flowing from the positive (high potential difference) plate to the from the positive (high potential difference) plate to the negative (low potential difference) plate.negative (low potential difference) plate.
The flow stops when the electric potential difference The flow stops when the electric potential difference between the two plates is zero.between the two plates is zero.
If the charge particles are pumped back to the original If the charge particles are pumped back to the original conductor (plate) by an outside energy source (battery), conductor (plate) by an outside energy source (battery), the flow of charges will continue.the flow of charges will continue.
Electric CircuitsElectric Circuits Any closed loop or conducting path allowing Any closed loop or conducting path allowing
electric charges to flow is called an electric electric charges to flow is called an electric circuit.circuit.
A circuit includes a charge pump and a device A circuit includes a charge pump and a device that reduces the potential energy of the charges that reduces the potential energy of the charges as they flow from one plate to another.as they flow from one plate to another.
The potential energy lost by the charges as they The potential energy lost by the charges as they move through the connected device is usually move through the connected device is usually converted to some other form of energy such as converted to some other form of energy such as kinetic (motor), light (lamp), or thermal (heater).kinetic (motor), light (lamp), or thermal (heater).
Requirements that must be Requirements that must be met to establish an electric met to establish an electric
current.current. There must be a closed conducting There must be a closed conducting
path that extends from the positive path that extends from the positive terminal to the negative terminal. It terminal to the negative terminal. It is not enough that there is simply a is not enough that there is simply a closed conducting loop; the loop closed conducting loop; the loop itself must extend from the positive itself must extend from the positive terminal to the negative terminal of terminal to the negative terminal of the electrochemical cell.the electrochemical cell.
Requirements (continued)Requirements (continued)
The second requirement of an electric The second requirement of an electric circuit that is common in each of the circuit that is common in each of the successful attempts is that there must successful attempts is that there must be an electric potential difference be an electric potential difference across the two across the two endsends of the circuit. This of the circuit. This is most commonly established by the is most commonly established by the use of an electrochemical cell, a pack use of an electrochemical cell, a pack of cells (i.e., a battery) or some other of cells (i.e., a battery) or some other energy source.energy source.
In SummaryIn Summary
In conclusion, there are two requirements that must In conclusion, there are two requirements that must be met in order to establish an electric circuit. The be met in order to establish an electric circuit. The requirements arerequirements are
1)There must be an energy supply capable of doing work 1)There must be an energy supply capable of doing work on charge to move it from a low energy location to a on charge to move it from a low energy location to a high energy location and thus establish an electric high energy location and thus establish an electric potential difference across the two ends of the potential difference across the two ends of the external circuit.external circuit.
2)There must be a closed conducting loop in the external 2)There must be a closed conducting loop in the external circuit that stretches from the high potential, positive circuit that stretches from the high potential, positive terminal to the low potential, negative terminal.terminal to the low potential, negative terminal.
When a battery no longer works, which When a battery no longer works, which requirement is not met?requirement is not met?
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1.1. An external energy supply to An external energy supply to pump the chargepump the charge
2.2. The external circuit must make The external circuit must make up a closed conducting loopup a closed conducting loop
3.3. Neither requirement is met.Neither requirement is met.
When a light bulb is burned out and no When a light bulb is burned out and no longer works, which requirement is not longer works, which requirement is not
met?met?
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1.1. An external energy supply to An external energy supply to pump the chargepump the charge
2.2. The external circuit must make The external circuit must make up a closed conducting loopup a closed conducting loop
3.3. Neither requirement is met.Neither requirement is met.
Electric CurrentElectric Current
CurrentCurrent is the rate at which charge flows past a is the rate at which charge flows past a point on a circuit.point on a circuit.
Current flows from the positive terminal to the Current flows from the positive terminal to the negative terminal.negative terminal.
Current (I) = q/t = Coulombs/sec=amperes (A)Current (I) = q/t = Coulombs/sec=amperes (A) Example: A 2 mm long cross section of wire is Example: A 2 mm long cross section of wire is
isolated and 20 C of charge is determined to pass isolated and 20 C of charge is determined to pass through it in 40 s. I = _____amperesthrough it in 40 s. I = _____amperes
Example: A 1 mm long cross section of wire is Example: A 1 mm long cross section of wire is isolated and 2 C of charge is determined to pass isolated and 2 C of charge is determined to pass through it in 0.5 s. I = ________amperesthrough it in 0.5 s. I = ________amperes
Current is measured in units of Current is measured in units of ______.______.
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1.1. AmperesAmperes
2.2. CoulombsCoulombs
3.3. VoltsVolts
4.4. OhmsOhms
The direction that conventional current flows in the The direction that conventional current flows in the external circuit is from the ___ terminal to the ____ external circuit is from the ___ terminal to the ____
terminal.terminal.
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1.1. negative, positivenegative, positive
2.2. positive, negativepositive, negative
3.3. negative, negativenegative, negative
4.4. positive, positivepositive, positive
Electrons move very quickly through Electrons move very quickly through an electric circuit.an electric circuit.
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1.1. TrueTrue
2.2. FalseFalse
If the current is measured as 6 A, then ____ If the current is measured as 6 A, then ____ C of charge flows past any point in the C of charge flows past any point in the
circuit in 3 s. circuit in 3 s.
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1.1. 0.50.5
2.2. 22
3.3. 33
4.4. 1818
PowerPower Power (measured in watts, W) measures the rate Power (measured in watts, W) measures the rate
at which energy is transferred. (1 W = 1J/s)at which energy is transferred. (1 W = 1J/s) The energy carried by an electric current depends The energy carried by an electric current depends
on the charge transferred and the potential on the charge transferred and the potential difference across which it moves.difference across which it moves.
Current is the rate of charge flow (I=q/t). A flow of Current is the rate of charge flow (I=q/t). A flow of 1 C/s is called an ampere (A).1 C/s is called an ampere (A).
Power is equal to the current times the potential Power is equal to the current times the potential difference.difference.
P = I VP = I V Total energy transferred = P x t (WTotal energy transferred = P x t (W..s or J)s or J)
Practice ProblemsPractice Problems
A 6.0 V battery delivers a 0.50 A A 6.0 V battery delivers a 0.50 A current to an electric motor current to an electric motor connected across its terminals.connected across its terminals.
What power is delivered to the What power is delivered to the motor?motor?
If the motor runs for 5.0 min, how If the motor runs for 5.0 min, how much electric energy is delivered?much electric energy is delivered?
The Kilowatt- HourThe Kilowatt- Hour
The electric company (power company) provides The electric company (power company) provides energy rather than power. energy rather than power.
When a bill is paid, the customer is paying for the When a bill is paid, the customer is paying for the electric energy used.electric energy used.
Because of the large amounts of energy Because of the large amounts of energy consumed, electric companies measure sales in a consumed, electric companies measure sales in a units of kilowatt-hours. units of kilowatt-hours.
One kilowatt hour is equal to 1000 W being One kilowatt hour is equal to 1000 W being delivered for 3600 s (1 hr) or 3.6 x 10delivered for 3600 s (1 hr) or 3.6 x 1066 J. J.
How many 100 W light bulbs would have to be How many 100 W light bulbs would have to be used for 1 full hour to consume 1 KWh of energy?used for 1 full hour to consume 1 KWh of energy?
Practice ProblemPractice Problem
An electric heater draws 15.0 A from a An electric heater draws 15.0 A from a 120 V source. It is operated, on the 120 V source. It is operated, on the average, for 5.0 h each day.average, for 5.0 h each day.
How much power does the heater use?How much power does the heater use? How much energy in KWh does it How much energy in KWh does it
consume in 30 days?consume in 30 days? At $0.12 per KWh, how much does it At $0.12 per KWh, how much does it
cost to operate the heater for 30 days?cost to operate the heater for 30 days?
ProblemProblem
A TV has a power rating of 103 W. A TV has a power rating of 103 W. How much does it cost per month to How much does it cost per month to operate it for 6 hours per weekday operate it for 6 hours per weekday and 15 hours/day on the weekend? and 15 hours/day on the weekend? (Assume a 4 week month)(Assume a 4 week month)
How much current does it draw?How much current does it draw?
Power is measured in units Power is measured in units calledcalled
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0%
0%
0% 1.1. amperesamperes
2.2. joulesjoules
3.3. kilowatt-hourskilowatt-hours
4.4. wattswatts
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Current is measured in units Current is measured in units calledcalled
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0%
0%
0% 1.1. amperesamperes
2.2. kilowatt-hourskilowatt-hours
3.3. potentialpotential
4.4. wattswatts
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If a 9.0 V battery delivers 0.50 A of If a 9.0 V battery delivers 0.50 A of current to a heater, the power current to a heater, the power
consumed by the heater isconsumed by the heater is
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0%
0%
0% 1.1. 0.056 W0.056 W
2.2. 4.5 W4.5 W
3.3. 9.0 W9.0 W
4.4. 18 W18 W
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If a light bulb is rated at 50 W, the If a light bulb is rated at 50 W, the amount of energy consumed in 30 amount of energy consumed in 30
minutes isminutes is
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0%
0%
0% 1.1. 2 kWh2 kWh
2.2. 30 kWh30 kWh
3.3. 30 J30 J
4.4. 90,000 J90,000 J
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The kilowatt-hour is a unit The kilowatt-hour is a unit of of
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0% 1.1. currentcurrent
2.2. energyenergy
3.3. potentialpotential
4.4. powerpower
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A 60 W light bulb illuminated A 60 W light bulb illuminated day and night for 30 days day and night for 30 days consumes ___ of energy,consumes ___ of energy,
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0%
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0% 1.1. 43.2 J43.2 J
2.2. 43.2 kWh43.2 kWh
3.3. 1800 kWh1800 kWh
4.4. 1.5 x 101.5 x 101212 kWh kWh
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If a family’s electric bill is $74.00 per If a family’s electric bill is $74.00 per month and the cost of electricity is month and the cost of electricity is
$0.12 per kWh, how much electricity $0.12 per kWh, how much electricity does the family use per month?does the family use per month?
0%
0%
0%
0% 1.1. 8.9 kWh8.9 kWh
2.2. 270 kWh270 kWh
3.3. 620 kWh620 kWh
4.4. 62000 kWh62000 kWh
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ResistanceResistance
Resistance (R) is a property that Resistance (R) is a property that determines how much current will determines how much current will flow.flow.
Resistance is measured in units Resistance is measured in units called ohms (called ohms (ΩΩ))
Factors Impacting Factors Impacting ResistanceResistance
LengthLengthResistance increases as length of wire Resistance increases as length of wire
increases.increases. Cross-sectional areaCross-sectional area
Resistance increases as cross-sectional area Resistance increases as cross-sectional area decreases.decreases.
TemperatureTemperatureResistance increases as temperature increases.Resistance increases as temperature increases.
MaterialMaterialResistance varies with the material used.Resistance varies with the material used.silver<copper<gold<aluminum<iron<platinumsilver<copper<gold<aluminum<iron<platinum
(in order of increasing resistance)(in order of increasing resistance)
Ohm’s LawOhm’s Law
Resistance is equal to potential Resistance is equal to potential voltage divided by current.voltage divided by current.
V = I RV = I R According to the law, 1 ohm is the According to the law, 1 ohm is the
resistance permitting an electric resistance permitting an electric charge of 1 A to flow when a charge of 1 A to flow when a potential difference of 1 V is applied potential difference of 1 V is applied across the resistance.across the resistance.
For a wire that obeys Ohm’s Law, For a wire that obeys Ohm’s Law, the resistance of a wire depends the resistance of a wire depends
on the ___ the wire.on the ___ the wire.
0%
0%
0%
0% 1.1. current incurrent in
2.2. length oflength of
3.3. power delivered bypower delivered by
4.4. voltage acrossvoltage across
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A battery with a voltage of 9.0 V is A battery with a voltage of 9.0 V is connected to a lamp. The current flowing in connected to a lamp. The current flowing in the circuit is 0.30 A. The resistance of the the circuit is 0.30 A. The resistance of the
lamp islamp is
0%
0%
0%
0% 1.1. 0.030 0.030 ΩΩ
2.2. 2.7 2.7 ΩΩ
3.3. 27 27 ΩΩ
4.4. 30 30 ΩΩ
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What factor impacting resistance explains What factor impacting resistance explains why light bulbs tend to burn out more why light bulbs tend to burn out more
frequently when they are first switched on frequently when they are first switched on rather than while they are operating?rather than while they are operating?
0%
0%
0%
0% 1.1. LengthLength
2.2. Cross-sectional areaCross-sectional area
3.3. TemperatureTemperature
4.4. MaterialMaterial
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Which wire conducts electricity Which wire conducts electricity with the least resistance?with the least resistance?
0%
0% 1.1. One with a large cross-sectional One with a large cross-sectional areaarea
2.2. One with a small cross-sectional One with a small cross-sectional areaarea
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World’s Longest Burning World’s Longest Burning LightLight
Livermore's Centennial Light
ResistorsResistors
Wires used to complete circuits have low resistance.Wires used to complete circuits have low resistance. A wire 1 m in length that is typically used in a A wire 1 m in length that is typically used in a
physics lab has a resistance of 0.03 physics lab has a resistance of 0.03 ΩΩ.. Wires used in home wiring offer as little as 0.004 Wires used in home wiring offer as little as 0.004 ΩΩ of of
resistance for each 1 m of length.resistance for each 1 m of length. Resistors are devices with specific resistances that Resistors are devices with specific resistances that
are used to control current in circuits or parts of are used to control current in circuits or parts of circuits.circuits.
A variable resistor (potentiometer) is used when a A variable resistor (potentiometer) is used when a smooth, continuous variation of the circuit is desired smooth, continuous variation of the circuit is desired (example: volume, brightness, contrast, hue, and (example: volume, brightness, contrast, hue, and tone controls on a TV)tone controls on a TV)
The human body acts as a variable resistor. (Dry skin The human body acts as a variable resistor. (Dry skin has high resistance-wet skin has lower resistance)has high resistance-wet skin has lower resistance)
A device that can be used to A device that can be used to change the current in a circuits change the current in a circuits
in a continuous way is a in a continuous way is a
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0% 1.1. potentiometerpotentiometer
2.2. batterybattery
3.3. motormotor
4.4. lamplamp
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If a 200 If a 200 ΩΩ resistor is connected resistor is connected to a 5 V battery, the current in to a 5 V battery, the current in
the circuit will be the circuit will be
0%
0%
0%
0% 1.1. 0.025 A0.025 A
2.2. 2.5 A2.5 A
3.3. 40 A40 A
4.4. 1000 A1000 A
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Types of CircuitsTypes of Circuits
There are three types of circuits:There are three types of circuits:Series circuits-all current travels Series circuits-all current travels
through each device.through each device.Parallel circuits-a circuit in which Parallel circuits-a circuit in which
there are several different current there are several different current pathspaths
Combination series-parallel Combination series-parallel circuit- circuits which includes both circuit- circuits which includes both series and parallel branches.series and parallel branches.
Series CircuitsSeries Circuits In a series circuit, the current is the same throughout.In a series circuit, the current is the same throughout.
IItotal total = I= IAA =I =IBB = I = ICC = … = … The equivalent resistance (total resistance) of the circuit The equivalent resistance (total resistance) of the circuit
equals the sum of the individual resistances of the equals the sum of the individual resistances of the resistors.resistors.
RRtotaltotal = R = RAA + R + RBB + … + … The total voltage is the sum of the individual voltages The total voltage is the sum of the individual voltages
across each device.across each device.
VVsourcesource = V = VAA + V + VBB + … + … If the voltage source does not change, adding more devices If the voltage source does not change, adding more devices
in series will decrease the current.in series will decrease the current. Because the current flows through one pathway, if one light Because the current flows through one pathway, if one light
goes out, they all go out.goes out, they all go out.
The current is ___ in a series The current is ___ in a series circuit.circuit.
0%
0%
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0% 1.1. higher at the beginning ofhigher at the beginning of
2.2. the same everywherethe same everywhere
3.3. lower at the beginninglower at the beginning
4.4. variable in variable in
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In a series circuit, the equivalent In a series circuit, the equivalent resistance is ___ any single resistance is ___ any single
resistance.resistance.
0%
0%
0%
0% 1.1. larger thanlarger than
2.2. determined bydetermined by
3.3. equal toequal to
4.4. smaller thansmaller than
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If the battery voltage does not If the battery voltage does not change, adding more devices in change, adding more devices in
the series ___ the current.the series ___ the current.
0%
0%
0%
0% 1.1. sometimes decreasessometimes decreases
2.2. always decreasesalways decreases
3.3. sometimes increasessometimes increases
4.4. always increasesalways increases
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To find the current through a To find the current through a series circuit, first calculate the series circuit, first calculate the
____.____.
0%
0%
0%
0% 1.1. voltagevoltage
2.2. equivalent resistanceequivalent resistance
3.3. powerpower
4.4. equivalent voltageequivalent voltage
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Parallel CircuitsParallel Circuits
A parallel circuit is one in which there are several paths.A parallel circuit is one in which there are several paths. The total current is the sum of the currents through The total current is the sum of the currents through
each path.each path.
IItotaltotal = I = IAA + I + IBB + I + Icc + … + … Placing two or more resistors in parallel always Placing two or more resistors in parallel always
decreases the equivalent resistance of a circuit.decreases the equivalent resistance of a circuit.1 1 = = 11 + + 11 + + 11 + … + …
R RR RAA R RBB R RCC
The potential difference across each path is the same.The potential difference across each path is the same.
VVtotaltotal = V = VAA = V = VBB = V = VCC = … = …
Safety DevicesSafety Devices
A short circuit occurs when a circuit with very low A short circuit occurs when a circuit with very low resistance is formed.resistance is formed.
Parallel circuits are susceptible to short circuits.Parallel circuits are susceptible to short circuits. Safety devices are incorporated into the circuit to Safety devices are incorporated into the circuit to
prevent a circuit overload.prevent a circuit overload.1. Fuse-a piece of metal melts when too much current 1. Fuse-a piece of metal melts when too much current flows and breaks the circuit.flows and breaks the circuit.
2. Circuit breaker-an automatic switch that opens 2. Circuit breaker-an automatic switch that opens when the current reaches a value greater than the when the current reaches a value greater than the rated value in the circuit.rated value in the circuit.
3. Ground-fault interrupter-an outlet that prevents 3. Ground-fault interrupter-an outlet that prevents injuries that are caused when an electric appliance injuries that are caused when an electric appliance falls into water. It contains an electric circuit that falls into water. It contains an electric circuit that detects an extra current path and opens the circuit.detects an extra current path and opens the circuit.
A 16.0 A 16.0 ΩΩ and a 20.0 and a 20.0 ΩΩ are connected are connected in parallel. 40.0 V is applied to the in parallel. 40.0 V is applied to the
combination.combination.
What is the equivalent resistance?What is the equivalent resistance? What is the total current in the What is the total current in the
circuit?circuit? What is the current in the 16.0 What is the current in the 16.0 ΩΩ
resistor?resistor? What is the power dissipated by the What is the power dissipated by the
16.0 16.0 ΩΩ resistor? resistor?
A heating coil has a resistance A heating coil has a resistance of 4.0 of 4.0 ΩΩ and operates on 120 and operates on 120
V.V. What is the current in the coil?What is the current in the coil? What is the power rating of the coil?What is the power rating of the coil? What energy is supplied to the coil if What energy is supplied to the coil if
it is operated for 30 min per day for it is operated for 30 min per day for 30 days?30 days?
At $.10 per kWh, how much does it At $.10 per kWh, how much does it cost to operate the coil for 1 month?cost to operate the coil for 1 month?
A 20.0 A 20.0 ΩΩ, 50.0 , 50.0 ΩΩ, and 10.0 , and 10.0 ΩΩ resistor resistor are connected in parallel to each are connected in parallel to each
other. 5.5 A of current flows through other. 5.5 A of current flows through the 20.0 the 20.0 ΩΩ. Resistor.. Resistor.
What is the voltage across the 20.0 What is the voltage across the 20.0 ΩΩ resistor?resistor?
What is the current through the 50.0 What is the current through the 50.0 ΩΩ resistor? resistor?
What is the current through the 10.0 What is the current through the 10.0 ΩΩ resistor? resistor?
What is the total current through the What is the total current through the circuit?circuit?
A person has a $5 and a 200 W stereo.A person has a $5 and a 200 W stereo.
At $0.15 per kWh, how many kWh can At $0.15 per kWh, how many kWh can the person use before the money runs the person use before the money runs out?out?
How many hours can the person How many hours can the person operate the stereo at this rate?operate the stereo at this rate?
If the stereo is plugged into a 120 V If the stereo is plugged into a 120 V outlet, what is the current flowing outlet, what is the current flowing through the stereo when it is operating?through the stereo when it is operating?
What is the resistance of the stereo?What is the resistance of the stereo?
A 22.0 A 22.0 ΩΩ lamp and a 4.5 lamp and a 4.5 ΩΩ lamp lamp are connected in series to a 45 V are connected in series to a 45 V
battery.battery. What is the equivalent resistance of What is the equivalent resistance of
the circuit?the circuit? What is the current in the circuit?What is the current in the circuit? What is the voltage drop across the What is the voltage drop across the
22 22 ΩΩ lamp? lamp? What is the power dissipated in the What is the power dissipated in the
22.0 22.0 ΩΩ lamp? lamp?
An ammeter is connected in series to a An ammeter is connected in series to a
10.0 V battery and a 5 10.0 V battery and a 5 ΩΩ and 15 and 15 ΩΩ
resistor.resistor. What should the ammeter read?What should the ammeter read? What is the power dissipated by the What is the power dissipated by the
circuit?circuit? How much energy is supplied by the How much energy is supplied by the
battery each minute?battery each minute? What is the voltage across each What is the voltage across each
resistor?resistor?
The load across a battery consists of The load across a battery consists of two resistors, 15 two resistors, 15 ΩΩ and 47 and 47 ΩΩ, ,
connected in series.connected in series.
What is the equivalent resistance?What is the equivalent resistance? What is the voltage in the 15 What is the voltage in the 15 ΩΩ
resistor if the current in the circuit resistor if the current in the circuit is .097 A?is .097 A?
What is the voltage in the 47 What is the voltage in the 47 ΩΩ resistor?resistor?
What is the voltage of the battery?What is the voltage of the battery?
A string of 18 identical holiday lights is A string of 18 identical holiday lights is connected in series to a 120 V source. connected in series to a 120 V source.
The string dissipates 64 W.The string dissipates 64 W.
What is the current that flows through What is the current that flows through the string?the string?
What is the equivalent resistance of What is the equivalent resistance of the light string?the light string?
What is the resistance of a single What is the resistance of a single light?light?
What power is dissipated by each What power is dissipated by each light?light?
A 30.0 A 30.0 ΩΩ resistor is connected in resistor is connected in series to two other 30.0 series to two other 30.0 ΩΩ
resistors connected in parallel.resistors connected in parallel. What is the equivalent resistance?What is the equivalent resistance? If the circuit is connected to a 1.5 V If the circuit is connected to a 1.5 V
battery, what is the total current that battery, what is the total current that flows through the circuit?flows through the circuit?
How much current flows through the How much current flows through the 30.0 30.0 ΩΩ that are connected in that are connected in
parallel?parallel?
Practice Problem #2Practice Problem #2
A 30.0 A 30.0 ΩΩ is wired in series with a 20.0 is wired in series with a 20.0 ΩΩ lamp. These two resistors are wired in lamp. These two resistors are wired in parallel with 10.0 parallel with 10.0 ΩΩ and 40.0 and 40.0 ΩΩ resistors resistors that are wired in series. All 4 of these that are wired in series. All 4 of these resistors are wired in series with a 25.0 resistors are wired in series with a 25.0 ΩΩ resistor and a 25 V battery.resistor and a 25 V battery.
1)1) Find the total resistance.Find the total resistance.
2)2) Find the current through each bulb.Find the current through each bulb.
3)3) Find the voltage drop across each bulb.Find the voltage drop across each bulb.
The current is the same The current is the same everywhere throughout the everywhere throughout the circuit.circuit.
0%
0% 1.1. ParallelParallel
2.2. SeriesSeries
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The total resistance is equal to The total resistance is equal to the sum of the individual the sum of the individual
resistances.resistances.
0%
0% 1.1. ParallelParallel
2.2. SeriesSeries
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The voltage drop across each The voltage drop across each resistor in the circuit is the resistor in the circuit is the
same.same.
0%
0% 1.1. ParallelParallel
2.2. SeriesSeries
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The voltage drop is the circuit The voltage drop is the circuit is proportional to the is proportional to the
resistance.resistance.
0%
0% 1.1. ParallelParallel
2.2. SeriesSeries
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Adding a resistor to the circuit Adding a resistor to the circuit decreases the total resistance.decreases the total resistance.
0%
0% 1.1. ParallelParallel
2.2. SeriesSeries
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Adding a resistor to the circuit Adding a resistor to the circuit increases the total resistance.increases the total resistance.
0%
0% 1.1. ParallelParallel
2.2. SeriesSeries
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If the current through one resistor If the current through one resistor goes to zero, there is no current in goes to zero, there is no current in
the entire circuit.the entire circuit.
0%
0% 1.1. ParallelParallel
2.2. SeriesSeries
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If the current through one resistor in If the current through one resistor in the circuit goes to zero, the current the circuit goes to zero, the current
through all of the other resistors through all of the other resistors remains the same.remains the same.
0%
0% 1.1. ParallelParallel
2.2. SeriesSeries
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This form is suitable for This form is suitable for household wiring.household wiring.
0%
0% 1.1. ParallelParallel
2.2. SeriesSeries
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An ammeter is connected in An ammeter is connected in ____ in a circuit.____ in a circuit.
0%
0% 1.1. ParallelParallel
2.2. SeriesSeries
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A voltmeter is connected in ___ A voltmeter is connected in ___ in a circuit.in a circuit.
0%
0% 1.1. ParallelParallel
2.2. SeriesSeries
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The basic unit of resistance is The basic unit of resistance is thethe
0%
0%
0%
0%
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1.1. voltvolt
2.2. ohmohm
3.3. ampamp
4.4. coulombcoulomb
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Electrical force of push is Electrical force of push is measured inmeasured in
0%
0%
0%
0% 1.1. coulombscoulombs
2.2. ohmsohms
3.3. ampsamps
4.4. voltsvolts
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A short thick wire has more A short thick wire has more resistance than a long thin resistance than a long thin
wire.wire.
0%
0% 1.1. TrueTrue
2.2. FalseFalse
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In a DC circuit, current flows from the In a DC circuit, current flows from the ___ electrode to the ___ electrode.___ electrode to the ___ electrode.
0%
0%
0%
0% 1.1. negative, positivenegative, positive
2.2. positive, negativepositive, negative
3.3. positive, positivepositive, positive
4.4. negative, negativenegative, negative
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