Term
| when two lamps are connected in series to a battery, the electrical resistance that the battery senses is |
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Definition
| more than the resistance of either lamp |
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Term
| when a 10-V battery is connected to a resistor, the current in the resistor is 2 A. what is the resistors value? |
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Definition
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Term
| a power line with a resistance of 2 ohms has a current of 80 A in it. the power dissipated in the line is |
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Term
| heat a copper wire and its electrical resistance |
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Definition
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Term
| the electric power of a lamp that carries 2 A at 120 V is |
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Definition
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Term
| the electric power of a lamp that carries 2 A at 120 V is |
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Definition
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Term
| the current through a 10 ohm resistor connected to a 120 v power supply is |
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Definition
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Term
| a circuit breaker often serves the same purpose as a |
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Definition
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Term
| a 100 watt lamp glows brighter than a 25 watt lamp. the electrical resistance of the 100 watt lamp must be |
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Definition
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Term
| a 10 ohm resistor has a 5 amp current in it. what is the voltage across the resistor? |
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Definition
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Term
| in a 110 v circuit containing a lamp in series with the voltage source, |
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Definition
| 110 joules of energy are given up by each coulomb of charge making up the current in the circuit |
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Term
| compared to the resistance of two resistors connected in a series, the same two resistors connected in parallel have |
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Definition
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Term
| stretch a copper wire so that it is thinner and the resistance between its ends |
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Definition
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Term
| on some early automobiles both headlights went out when one burned out. the headlights must have been connected in |
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Definition
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Term
| compared to a single lamp connected to a battery, two lamps connected in parallel to the same battery will carry |
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Definition
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Term
| an ampere is a unit of electrical |
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Definition
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Term
| a 60 W light bulb and a 100 W light bulb are each rated at 120 V. which light bulb has a larger resistance? |
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Definition
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Term
| a 60 W light bulb and a 100 W light bulb are connected in series to a 120 V outlet. which light bulb has more current in it? |
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Definition
| both have the same current. |
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Term
| unit used for electrical resistance |
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Definition
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Term
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Definition
| the flow of electric charge |
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Term
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Definition
| electrons from each metal atom that are free to move throughout the atomic lattice |
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Term
| one ampere is a rate of flow equal to |
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Definition
| one coulomb of charge per second |
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Term
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Definition
current = voltage/resistance
(amps = volts/ohms) |
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Term
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Definition
| electrons in the circuit are moved first in one direction and then in the opposite direction, alternating to and fro about relatively fixed positions |
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Term
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Definition
| flowing of charges in one direction. a battery produces direct current - electrons move from the repelling negative terminal toward the attracting positive terminal. |
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Term
| the standard ac voltage in north america |
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Definition
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Term
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Definition
power = current x voltage
(watts = amperes x volts) |
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Term
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Definition
1. electric current has only a single pathway through the circuit. (meaning current passing through the resistance of each electrical device along the pathway is the same).
2. this current is resisted by the resistance of the first device, the second, and the third, so the total resistance to current in the circuit is the sum of the individual resistances along the path.
3. the current in the circuit is numerically equal to the voltage supplied by the source divided by the total resistance of the circuit. (ohms law)
4. supply voltage is = the sum of the individual 'voltage drops' across each device.
5. the voltage drop across each device is proportional to its resistance. |
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Term
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Definition
1. each device connects the same two points of the circuit. voltage is the same across each device.
2. the current divides among the parallel branches. ohms law applies separately to each branch.
3. total current in the circuit = the sum of the currents in its parallel branches. this sum = current in the battery or other voltage source.
4. as the # of parallel branches increases, overall resistance decreases. |
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