AC/DC Finals Part 1 CH 6-10

True

A short-circuited branch circuit has a resistance of zero.

False

A voltage multiplier is a circuit made of resistors connected in series to produce a desired voltage drop across the resistors.

False

An open circuit is the same as a series circuit in that any open point in the circuit causes electron flow to stop.

True

Certain types of electronic systems require both a positive and a negative source of voltage for proper operation.

True

Conductance is improved and resistance reduced when adding resistors in parallel.

current

Current distribution in parallel-connected circuits equals the sum of the ____________________ through all branch circuits.

series

Current has the same value at any point in a(n) ____________________ circuit.

electrons

Current is the flow of ____________________ through an electrical circuit.

double

Doubling the number of conductors in parallel will ___ the electron flow in a circuit.

True

Efficiency of a circuit can be determined by dividing the power at the load by the total power output.

open

Electron flow is interrupted in a(n) ____________________ circuit.

True

Electrons have bodies that can be counted.

True

Heat is produced when electrons flow through a wire that has resistance.

power

Maximum ___ transfer between a source and load depends on the load resistance matching the source resistance.

False

More power is produced when a load's resistance is high or its applied voltage is low.

False

Not all sources of electrical potential have internal resistance.

voltage

Ohm's law can be used to calculate the ____________________ drop across any resistor.

False

Ohm's law can be used to calculate total circuit voltage and current, but not total circuit resistance.

False

Opening a series circuit at any point will increase the flow of electrons.

True

Parallel circuits are used when a constant current flow from a voltage source is needed.

False

Power is measured in ohms.

True

Resistors are available with a variety of power ratings.

False

Some electrical sources have no internal resistance.

3

The National Electrical Code® suggests that conductors be sized so that they do not reduce the voltage at the load by more than ____________________% of the source voltage.

200

The actual voltage of a 208 V circuit with a load resistance of 25 Ω and load current of 8 A is ___ V.

7.21

The total current in a parallel circuit that has 208 V applied to it and produces 1500 W of power is ___ A.

120

The total power in a circuit if six loads are connected in series and each load produces 20 W is ___ W.

5.1

The total resistance in a circuit containing resistors of 10 Ω, 15 Ω, and 35 Ω connected in parallel is ___ Ω.

0.98

The total resistance in a circuit containing resistors of 2 Ω, 3 Ω, and 5 Ω connected in parallel is ___ Ω.

1.875

The total resistance in a circuit containing resistors of 3 Ω and 5 Ω connected in parallel is ___ Ω.

6.06

The total resistance in a circuit containing resistors of 8 Ω and 25 Ω connected in parallel is ___ Ω.

stays the same

The voltage drop in a parallel circuit ___ across each load.

True

Total current in a parallel circuit is calculated by adding the current in all the branches.

True

Voltage drop is proportional to the resistance value of the resistors in a series circuit.

False

Whenever the load resistance is matched to the source, less than maximum power is delivered to the load.

open

Zero current flow in a circuit indicates that there is a(n) ____________________ between the power source and a load or switch in the circuit.

power source

Zero current flow may indicate an open between the ___ and a load or switch in the circuit.

voltage divider

A ___ is a circuit that is constructed by connecting resistors in series to produce a desired voltage drop across the resistors.

True

A complex circuit includes two or more resistive loads.

electrons

A ground is an unlimited source and acceptor of ___ in a circuit.

True

A listed power rating is given in watts (W) for most appliances or in horsepower (HP) for motors.

horsepower

A power rating is listed in watts for appliances and in ____________________ for motors.

False

A series circuit has two current paths.

parallel

A(n) ____________________ circuit has two or more loads and more than one path for electron flow.

ground

A(n) ____________________ is a low-resistance conducting connection between electrical and electronic circuits, equipment, and the earth.

short circuit

A(n) ____________________ is any circuit in which current takes a shortcut around the normal path of current flow.

ballast

A(n) ____________________ resistor may be added to a parallel circuit to produce a constant flow of current.

False

As loads are added in parallel, the total current decreases.

True

As the resistance of a load decreases, the amount of power produced increases.

True

Assuming that power at each load in a series circuit is known, total power can be calculated by adding the power at each load.

True

If one component in a parallel circuit has a short circuit, the total resistance of the circuit is reduced to 0 Ω.

485

If six loads are connected in parallel and the loads produce 60 W, 75 W, 100 W, 150 W, 60 W, and 40 W, the total circuit power is ___ W.

0.37

If the current in each branch in a parallel circuit is 0.3 A and 0.07 A, the total current is ___ A.

33.95

If the current through four loads connected in parallel in a circuit is 0.221 A, 16.73 A, 3.3 A, and 13.7 A, the total current is ___ A.

20.67

If the current through four loads connected in parallel in a circuit is 0.522 A, 10.25 A, 7 A, and 2.9 A, the total current is ___ A.

24

If the voltage drop across two loads connected in parallel is 24 V, the total applied voltage in the circuit is ___ V.

3

If the voltage drop across two loads connected in parallel is 3 V, the total applied voltage in the circuit is ___ V.

True

In a DC parallel circuit, electrons flow in one direction.

VT

In a complex circuit, the source voltage is designated as ___.

branch

In a parallel circuit, each load is called a(n) ___ circuit.

False

In a parallel circuit, the voltage drop across each load can be different.

False

In a series circuit, the sum of the voltage increases is equal to the source voltage.

False

In a series circuit, there are three paths for electron flow.

0

The current through a short circuit can be any value because the resistance of the short circuit is always equal to ____________________ Ω.

True

The lower a load's resistance, the more power produced in a series circuit.

201.76

The minimum allowable voltage at the load of a 208 V circuit with a load resistance of 25 Ω and load current of 8 A is ___ V.

36

The supply voltage in a series circuit containing a total resistance of 3 Ω and total current of 12 A is ___ V.

75

The supply voltage in a series circuit containing a total resistance of 5 Ω and total current of 15 A is ___ V.

0.0077

The total current flow and the current flow through each branch of a circuit that has a total voltage of 15 V connected in parallel with a 3.5 kΩ resistor and a 4.4 kΩ resistor is ___ A.

2.2

The total resistance in a parallel circuit that has a total current of 5.5 mA and a total voltage of 12 V is ___ kΩ.

24

The voltage drop across a 2 Ω resistor in a circuit that has a total current of 12 A is ___ V.

16D.64

The voltage drop across an 8 Ω resistor in a circuit that has a total current of 8 A is ___ V.

28.8

The voltage in a parallel circuit branch that has a resistor of 3.6 kΩ and a current of 8 mA flowing through it is ___ V.

33

The voltage in a parallel circuit branch that has a resistor of 5.5 Ω and a current of 6 A flowing through it is ___ V.

added

To find total resistance in a series circuit, the values of the resistors in the circuit are ___.

False

Total current decreases if parallel loads are added and increases if parallel loads are removed.

sum

Total power of a parallel circuit is equal to the ____________________ of the power produced by each load.

power

Total voltage multiplied by total circuit current yields total ____________________ in a circuit.

False

Using parallel power distribution permits various loads to be connected to different power sources.

drop

Voltage ___ is the amount of voltage used by a device when current passes through it.

False

When a DMM set to measure current is inserted in series at every junction of the components in a series circuit, it reads a different current value at each junction.

True

When current takes a shortcut around the normal path of current flow, it is referred to as a short circuit.

reciprocal

When only two resistors are in parallel, the ___ method reduces to the product over the sum of the resistor values.

Current

When selecting a heating element for an application, the size of the heating element is typically stated in ____________________ and is based on the application.

Current

___ is the flow of electrons through an electrical circuit.

Heat

____________________ is produced any time electrons flow through a wire that has resistance.

Voltage drop

____________________ is the amount of voltage consumed by a component as current passes through it.

Resistance

____________________ is the opposition to electron flow.

Power

____________________ produced is measured in watts (W).