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What is the function of resistor in a circuit board?
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Drift velocity is the net velocity of a charge carrier moving in
an electric field. In a copper wire that has a current of 10.0 A,
the drift velocity of electrons is only 2.46x10-4 m/s. These
electrons would take about 68 minutes to travel 1 meter. How does
the light bulb go on instantly when you turn the switch on?
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The current in a light bulb is 0.835 A. How long does it take for
a total charge of 1.67 C to pass through the filament of the
bulb?
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In a metal conductor, current is the result of moving electrons.
Can charge carriers ever be positive?
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Is current ever "used up"? Explain your answer.
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In a particular television tube, the beam current is 60.0 ~. How
long does it take f~r 3.7SX10~ electrons to strike the screen?
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7.
The resistance of a steam iron is 19.0 n. What is the current in
the iron when it is connected across a potential difference of
120 V?
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The current on a microwave oven is 6.25 A. If the resistance of
the oven's circuitry is 17.6 0, what is the potential difference
across the oven?
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An ammeter registers 2.5 A of current in a wire that is connected
to a 9.0 V battery. What is the wire's resistance?
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10'~ Calculate the current in a 75
n resistor when a potential
difference of 115 V is placed across it. What will the current be
if the resistor is replaced with a 47-0 resistor?
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Using the atomic theory of matter, expla~n why the resistance of
a material should increase as its temperature increases.
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Calculate the resistance of a 4'.00meter Length of a cooper ,wire
having a diameter of 2.00 millimeters. Assume a temperature of
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13.
A 5.00 meters-long tin wire has a cross-sectional area of
2.00x10-6 m2 and a resistance of 0.35 ohm. Calculate the
resistivity of this tin wire.
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An aluminum wire and a tungsten wire have the same crosssectional area and the same resistance at 20° C. If the aluminum
wire is 4. 0x10-2 meter long, what is the length of the tungsten
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A color television has a power rating of 325 W. How much current
does this set draw from a potential difference of 120 V?
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The headlights on a car ar~ rated at 80.0 W. If they are
connected to a fully charged 90.0 A·h, 12.0 V battery, how long
does it take the battery to completely discharge?
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A compute'r-is -connect ed across a 110 V power supply. The computer
dissipates 130 W of power in the form of electromagnetic
radiatien and heat. Calculate the resistance of the computer.
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A student in your class claims that batteries work by supplying
the charges that move in a conductor, generating a current. What
is wrong with this reasoning?
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