Deck 11: Network Theorems

Question 1

Of all the network theorems, ______________ theorem is by far the most widely used.

Answer 1

Thevenin's

Question 2

A current source symbol with a dashed or broken arrow indicates the direction of ______________ current flow.

Answer 2

electron

Question 3

______________ theorem is used to simplify a network in terms of currents instead of voltages.

Answer 3

Norton's

Question 4

______________ a current source kills its ability to supply current without affecting any parallel branches.

Question 5

______________ theorem says that any network can be represented by a voltage source and a series resistance.

Question 6

An ideal current source is assumed to have an internal resistance of ______________ ohms.

Question 7

In general, a current source is ______________ by opening the path between its terminals.

Question 8

______________ theorem provides a shortcut for finding the common voltage across any number of parallel branches with different voltage sources.

Question 9

Delta (or Wye) ______________ are generally used in three-phase ac power circuits.

Question 10

When all the R values are equal in a network, it is ______________.

Question 11

A current source symbol which uses a solid arrow indicates

A) the direction of electron current flow
B) the direction of conventional current flow
C) the polarity of the voltage source
D) that the current is above 1 amp

Question 12

Norton's theorem is used

A) for ac circuits only
B) for dc circuits only
C) to simplify a network in terms of voltages
D) to simplify a network in terms of currents

Question 13

What supplies a total line current to be divided among parallel branches?

A) Generator
B) Voltage source
C) Current source
D) Battery

Question 14

Another term for opening a current source is to

A) kill it
B) murder it
C) short it
D) break it

Question 15

What theorem or law states that an entire network can be replaced by a single current source in parallel with a single resistance?

A) Superposition
B) Kirchhoff's law
C) Thevenin's theorem
D) Norton's theorem

Question 16

The Thevenin voltage (V_TH) is equal to

A) I_N x R_N
B) I_T x R_T
C) I_TH x R_TH
D) P_N / I_N

Question 17

What is a specific example of the general principle that any voltage source with its series resistance can be converted to an equivalent current source with the same resistance in parallel?

A) Thevenin conversion
B) Norton conversion
C) Kirchhoff conversion
D) Ohm's conversion

Question 18

With appropriate values known, voltage can be calculated as

A) R/I
B) P/R
C) I/G
D) R x G

Question 19

What theorem or law provides a shortcut for finding the common voltage across any number of parallel branches with different voltage sources?

A) Kirchhoff's
B) Norton's
C) Superposition
D) Millman's

Question 20

Delta and wye networks are often used in circuits involving

A) bridge circuits
B) power supplies
C) three-phase ac power
D) single-phase ac power

Question 21

Passive networks have

A) no energy sources
B) amplifiers
C) batteries
D) constant current sources

Question 22

When all the R values are equal in a network,

A) total resistance is zero
B) it is balanced
C) total resistance is infinite
D) it becomes a delta network

Question 23

A combination of components, such as resistances, interconnected to achieve a particular end result is a

A) oscillator
B) rectifier
C) branch
D) network

Question 24

Network theorems can be applied to

A) dc circuits only
B) ac circuits only
C) dc and ac circuits
D) three-phase ac only

Question 25

What theorem or law states that in a network with two or more sources, the current or voltage for any component is the algebraic sum of the effects produced by each source acting separately?

A) Ohm's
B) Kirchhoff's
C) Superposition
D) Millman's

Question 26

While using superposition, disabling a source so that it cannot generate voltage or current without changing the resistance of the circuit is called

A) killing a source
B) breaking a source
C) opening a source
D) blocking a source

Question 27

In order to superimpose currents and voltages, all components must be

A) nonlinear and bilateral
B) linear and unilateral
C) linear and bilateral
D) diodes and transistors

Question 28

When the current is proportional to the applied voltage, it is

A) bilateral
B) unilateral
C) linear
D) nonlinear

Question 29

When the current is the same amount for opposite polarities of the source voltage, it is

A) bilateral
B) unilateral
C) linear
D) nonlinear

Question 30

Components that do not amplify or rectify are called

A) passive
B) active
C) nonlinear
D) transistors

Question 31

What theorem or law states that the entire network connected to A and B can be replaced by a single voltage source in series with a single resistance?

A) Kirchhoff's
B) Thevenin's
C) Norton's
D) Millman's

Question 32

The accepted assumption is that an ideal voltage source has an internal resistance of

A) 0 ?
B) 75 ?
C) 300 ?
D) ? ?

Question 33

Components such as transistors, semiconductor diodes, and electron tubes are

A) passive
B) linear
C) bilateral
D) active

Question 34

A network is a combination of components, such as resistances, interconnected to achieve a particular end result.

Question 35

Network theorems usually provide shorter methods than Kirchhoff's laws for solving a circuit.

Question 36

Theorems cannot be applied to ac networks.

Question 37

The superposition theorem states that in a network with two or more sources, the current or voltage for any component is the algebraic sum of the effects produced by each source acting separately.

Question 38

The expression, temporarily killing a source means disabling the source so that it cannot generate voltage or current without changing the resistance of the circuit.

Question 39

All components must be nonlinear and unilateral to superimpose currents and voltages.

Question 40

When using superposition, linear means that the current is proportional to the applied voltage.

Question 41

When using superposition, bilateral means that the current is the same amount for opposite polarities of the source voltage.

Question 42

Networks with resistors, capacitors, and air-core inductors are generally linear and bilateral.

Question 43

Of all the different theorems, the superposition theorem is by far the most widely used.

Question 44

By Thevenin's theorem, many sources and components can be represented by an equivalent series circuit with respect to any pair of terminals in the network.

Question 45

The Thevenin equivalent circuit driving terminals A and B changes whenever R_L changes.

Question 46

In general, a circuit can often be simplified by disconnecting a component to open terminals A and B for Thevenin's theorem.

Question 47

Thevenin's theorem cannot be used to find the current through a resistor that is in the center of a bridge circuit.