Series/Parallel Resistive Circuits

Question 1

What is a schematic diagram?

Answer 1

Schematic diagrams are electrical drawings that show components in their electrical sequence (or scheme) without regard for physical location.

Question 2

Schematic diagrams can also be called ___ diagrams.

Answer 2

circuit diagrams, ladder diagrams or ladder logic.

Question 3

What 2 things are electrical diagrams made up of?

Answer 3

1. Symbols that represent the components in the circuit and

2. lines that represent connections between the components

Question 4

A series circuit must be drawn in a schematic style.

True or False

Answer 4

False

Question 5

The opposition a material offers to current flow due to its structure is called what?

Answer 5

Resistance

Question 6

What is resistance measured in?

Answer 6

Ohms, Ω

Question 7

If the circuit only has one path for current to flow along it is a ___ circuit.

Answer 7

series

Question 8

Never measure the resistance of any energized object or circuit.

True or False

Answer 8

True

Question 9

What is an ohmmeter?

Answer 9

A device that measures resistance in an electronic component or circuit. It can also be part of another electrical testing device called a multimeter.

Question 10

What is an open circuit?

Answer 10

A circuit with a continuity break

Question 11

The equation of resistance in a series circuit is what?

Answer 11

R˕=R₁+R₂+R₃+…

Transposed:
R₂=R˕-R₁-R₃.

Question 12

What is potential difference?

Answer 12

A difference in electric pressure between two points in an the electric circuit. Measured in volts (V).

Question 13

What is a closed loop?

Answer 13

It’s a circuit drawing style, often referred to as a closed circuit.

Question 14

What is Kirchhoff’s Voltage Law?

Answer 14

It states that the algebraic sum of all voltages in a closed loop must equal zero. The mathematical equation is
E-V₁-V₂-V₃=0V. It also states that the applied voltage must equal the sum of the voltage drops. E=V₁+V₂+V₃+…

Question 15

What is current?

Answer 15

The flow of electrons past any point in a given period of time in an electric circuit. The measurement for current is an ampere (A).

Question 16

What is the device that measures current in a circuit?

Answer 16

An ammeter

Question 17

The mathematical equation for current in a series circuit is what?

Answer 17

I˕=I₁=I₂=I₃

Question 18

What is a ratio?

Answer 18

A comparison of two like quantities. One thing compared to or related to another thing; it is just a statement or an expression.

Question 19

What is a proportion?

Answer 19

Two equal ratios. A proportion is an equation that can be solved.
eg. 1:2=2:4
(The two inside terms are the means, and the two outside terms are the extremes)

Question 20

In direct proportion, changing one quantity (or number) changes the other quantity (or number) by the same ratio.

True or False

Answer 20

True

Question 21

What is an indirect proportion? (also called an inverse proportion)

Answer 21

And indirect proportion occurs when increasing one quantity decreases the other quantity or when decreasing one quantity also increases the other.

Question 22

What is the voltage divider rule?

Answer 22

The rule states the voltage divided between series resistors is directly proportional to the resistance of the resistors.

Question 23

What can the voltage divider rule be used to solve?

Answer 23

Simple series circuits

Question 24

If you were to connect a voltmeter across a closed switch in a series circuit what would the meter read?

Answer 24

0 V

Question 25

In an open series circuit, the voltage drop across the switch equals the applied voltage.

True or False

Answer 25

True

Question 26

What is a parallel circuit?

Answer 26

A circuit which current can flow through more than one path or branch.

Question 27

What is the mathematical equation for voltage in a parallel circuit?

Answer 27

E=V₁=V₂=V₃=…

Question 28

In parallel circuits, each resistance load added in parallel to the circuit ____ total current flow and ____ the total resistance of the circuit.

Answer 28

increases, decreases

Question 29

In a parallel circuit, the total resistance is always less than the lowest resistance value of any branch.

True or False

Answer 29

True

Question 30

What is the mathematical equation for resistance in a parallel circuit?

Answer 30

R˕=_____1______
1 1 1
R₁+R₂+R₃+…

Question 31

What is Kirchhoff’s Current Law?

Answer 31

The algebraic sum of currents entering and leaving a junction point in a closed circuit is zero. Also, that all current values entering a junction point must equal all current values leaving the junction point.

Question 32

What is the mathematical equation for current in a parallel circuit?

Answer 32

I˕=I₁+I₂+I₃+…

Question 33

When an open circuit occurs in a parallel circuit, the total line current of the circuit ____ and the total resistance of the circuit ____.

Answer 33

decreases, increases.

Question 34

Four resistors are connected in series. If one of the resistors becomes open, the resistance of the circuit would now be:

a) zero ohms
b) the sum of the other 3 resistors
c) infinite

Answer 34

c) infinite

Question 35

What is the unit of measurement for dielectric strength?

Answer 35

Volts per mm

Question 36

Which has the lowest resistance?

a) Silver
b) Iron
c) Copper
d) Aluminum

Answer 36

a) Silver

Question 37

A parallel circuit consists of two resistors, if the ohmic value of R2 is decreased then the current through R1 will:

a) increase
b) decrease
c) stay the same

Answer 37

c) stay the same