Ch. 3 Electricity Flashcards Preview

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Flashcards in Ch. 3 Electricity Deck (30)
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1

The resistance in a wire decreases as its:

Diameter increases

2

If the total resistance in a circuit is 9 ohms and the total voltage is 3 volts, the current it:

1/3 amperes.
V=IR

3

If a DC circuit is:
a. In series, the currents are different for each component
b. In series, the voltages are the same for each compartment
c. In parallel, the currents are equal for all paths of the circuit
d. In parallel, the voltages are equal for all paths of the circuit

d. In parallel, the voltages are equal for all paths of the circuit

4

Electric current is defined as:

Charge/time

5

Coulomb's law of electrical forces is mathematically described as:

F=q1q2/r^2

6

A current of 2 amperes and a resistance of 8 ohms require what voltage in a series circuit?

16 volts
V=IR

7

When an electric current flows through a wire with resistance, energy is:

liberated as heat

8

Ohm's law is mathematically described as:

R=V/I
(or V=IR)

9

Electric potential is measured in:

Volts

10

Electric insulators:

Inhibit movement of electrical charge

11

If 20 volts of potential difference causes a current of 5 amperes to flow in a parallel circuit, the resistance produced is:

4 ohms
V=IR

12

When the atomic valence and conductance bands overlap,

Electrical flow easily occurs

13

A charge would lost most of its energy when it passes through a:

Resistor

14

If the distance between two electrical charges is doubled, the force between them is:

Decreased by 1/4

15

A 100 W light bulb with an amperage of 0.91 A is operating at a potential difference of:

110 volts

16

An ampere is:

Coulomb/sec

17

Resistance is:

The opposition to the flow of electrons

18

The charge on each of two objects is doubled, and they are moved twice as far apart. The force between them is:

Unchanged

19

A circuit has a current of 2 amperes and a resistance of 4 ohms. The maximum power that can be delivered is:

16 Watts
V=IR
P=IV
or P=I^2(R)

20

The unit of electrical power is:

Watt

21

If 10 coulombs pass a point in 2 seconds, the current is:

5 amps (Couloumb/second)

22

In a parallel circuit,

The voltage is equal across all branches of the circuit.

23

In a battery circuit with several resistors of different values connected in series,
a. The voltage drop is the same across all the resistors
b. The current through each resistor is different
c. The power dissipated through each resistor is the same
d. None of the above

d. None of the above

24

If a conductor is positively charged, it:

Is deficient in electrons

25

The milliampere (mA) is a unit of:

Current

26

Neon lights illustrate the fact that electrons will flow:

In a gaseous environment

27

All of the following choices are considered good metallic electrical conductors EXCEPT:
a. Gold
b. Silver
c. Carbon
d. Copper

c. Carbon

28

The current flow from a dry cell battery source would be:

Direct current

29

Electrical components possess a negative and a positive side. This polarity permits the application of:

An electromotive force (emf) to enable current flow

30

When 6.24 x 10^18 electrons travel in one second producing a joule (j) of work,

One volt has been created