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The flashcards below were created by user
iishvo
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A device that produces electricity by transforming chemical energy into electrical energy is called a
battery

A car battery
has an emf of 12 V consisting of six 2V cells connected in series.

The total amount of charge that passes through a wire's full cross section at any point per unit of time is referred to as
current

The direction of convention current is taken to be the direction that
positive charges would flow.

A coulomb per second is the same as
an ampere.

Car batteries are rated in "amphours." This is a measure of their
charge

The resistance of a wire is defined as
voltage/current

What is 1 Ohm equivalent to?
1 V/A

The resistance of a wire is
proportional to its length and inversely proportional to its crosssectional area

The resistivity of a wire depends on
the material out of which it is composed.

Which conducting material has the lowest resistivity value?
silver

Consider two copper wires. One has twice the length of the other. How do the resistivities of these two wires compare?
Both wires have the same resistivity.

Consider two copper wires. One has twice the length of the other. How do the resistances of these two wires compare?
The longer wire has twice the resistance of the shorter wire.

Consider two copper wires. One has twice the crosssectional area of the other. How do the resistances of these two wires compare?
The thicker wire has half the resistance of the shorter wire.

Consider two copper wires. One has twice the length and twice the crosssectional area of the other. How do the resistances of these two wires compare?
Both wires have the same resistance.

The length of a wire is doubled and the radius is doubled. By what factor does the resistance change?
half as large

How much more resistance does a 1.0 cm diameter rod have compared to a 2.0 cm diameter rod of the same length and made of the same material?
300%

The resistivity of most common metals
increases as the temperature increases.

Negative temperature coefficients of resistivity
exist in semiconductors

What is 1 W equivalent to?
1 V*A

A kilowatthour is equivalent to
3,600,000 J

If the resistance in a constant voltage circuit is doubled, the power dissipated by that circuit will
decrease to onehalf its original value.

If the voltage across a circuit of constant resistance is doubled, the power dissipated by that circuit will
quadruple

If the resistance in a circuit with constant current flowing is doubled, the power dissipated by that circuit will
double

If the current flowing through a circuit of a constant resistance is doubled, the power dissipated by that circuit will
quadruple

