RAWS Block 2

Ohm's law equation

I = E/R

What does Ohms law calculate?

Voltage, Current, Resistance

Electrons always flows from which point to which point

Negative to Positive

What does a resistor do?

Provides a load (resistance)

Power is measured in what units?

Watts

Symbol for Voltage

E

What is E(sub)a

Applied Voltage (A battery)

Kirchoff's Current Law

says the rate of flow is continuous at any point in the circuit

What is a Voltage Drop?

Pressure caused by resistors

Kirchhoff's Voltage Law

says the voltage drops (caused by resistors) will always equal the applied voltage (Battery)

Symbol for Resistance

R

Resistance is measured in what?

Ohms

These are neither good or bad for conducting

Semiconductors

Does not allow electrons to move easily

Insulators

Allows electrons to flow easily

Conductors

An electromotive force(EMF) is also known as

Voltage

Neutrons are ___ charged

no charge

Electrons are ___ charged

negatively

Protons are ___ charged

positively

Valence electrons are on the ____ of the nucleus

outer band

If you lose or gain an electron, it is called an

Ion

Symbol for Current is

I

The unit of measure for current is

Amperes, Amps, A

Adjusting the decimal point in order to get the exponent to a multiple of 3 is what kind of notation

Engineering Notation

Adjusting the decimal point in order to get only one digit to be 1-9 is what kind of notation

Scientific Notation

A fuse

What symbol does this represent?

a circuit breaker

What symbol does this represent?

a resistor

What symbol does this represent?

a switch

What symbol does this represent?

If everything is connected through 1 path and the current is common, what kind of circuit is it?

Series Circuit

If the current flow divides and then comes back together and the voltage is common, what kind of circuit is it?

Parallel Circuit

This kind of circuit contains both types circuits in one

Series-Parallel Circuit

The greater the opposition to current flow, the greater the ____

Resistance

4 Factors that affect Resistance

Material, Length, Cross-Sectional Area, Temperature

Temperature up, Resistance up =

Positive Temperature Coefficient

Temperature up, Resistance down =

Negative Temperature Coefficient

Length affects the resistance in that it is ___ proportional

Directly

Cross-sectional area affects resistance in that it is ___ proportional

Inversely

3 Types of Resistors

Fixed, Variable, Tapped

Fixed Resistors have what kind of value?

a Set Value

Name 2 types of variable resistors

Rheostat, Potentiometer

Rheostat

Varies the Current

Potentiometer

Varies the Voltage

Equivalent Resistance

found when you calculate parallel resistance on a series-parallel circuit.

Load refers to

Current

Chassis Ground Symbol

What symbol does this represent?

Ground Symbol

What symbol does this represent?

According to Ohms Law if Current increases, Voltage must do what?

Increase

According to Ohms Law if Resistance increases, Voltage and Current must do what?

Decrease

Potentiometer

What symbol is this?

Rheostat

What symbol is this?

moving the decimal place of the numerical coefficient to the left makes the exponent more

positive

in engineering notation, exponents are either zero or multiples of _

3

arrange metric prefixes in order from smallest to largest

pico, micro, kilo, mega, giga, tera

what is the metric prefix and symbol for 10*0

no prefix or symbol

metric prefixes increase by a factor of ____ times larger than the last one

1,000

using a metric prefix, 30,000 is expressed as _

30K

using a metric prefix, 40,000,000 is expressed as

40M

more protons than electrons

positive ion

more electrons than protons

negative ion

equal number of protons and electrons

electrically neutral atom

what describes the flow of free electrons within a conductor

with the application of an electrical force, free electrons will move in the same direction

the flow of electrons through a conductor is called

current

the rate of electron movement in a conductor is measured in

amperes

in a circuit,electrons will move from the most ____ point to the most ____ point

negative, positive

what best describes a conductor

a material containing many free electrons

example of a conductor

copper

what best describes a insulator

a material containing few free electrons

example of a insulator

plastic

a is neither a good conductor or good insulator

semiconductor

an electrical force is required for the flow of electrons through a conductor. this is called

voltage

a difference of potential which causes current to flow is called

voltage

unit of measure for voltage

volt

symbol for current

I

unit of measure for current

ampere

symbol for unit of measurement for voltage

V

symbol for voltage

E

resistance is

opposition to current

power is the rate of

doing work

the watt is the unit of measure for

power

the term ____ may refer to a common reference point in a electrical circuit or path to an energy source

ground

battery

fuse

voltmeter

switch

ammeter

ohmmeter

how many particles make up an atom

three

to simplify a large number, the decimal point is moved to the

left

what is true about resistance

resistance is necessary to control circuit current

according to ohms law

current equals voltage divided by resistance

kirchoff's voltage law in a series circuit states that the

voltage is divided up among individual resistors, according to their value

when a branch is added to a parallel circuit what happens

the applied voltage does not change

in a series-parallel circuit

total current flows through the series component

characteristics of series circuit

current is common

voltage is divided

has one path

law that states the current in a circuit is directly proportional to the applied voltage and inversely proportional to the resistance

ohms law

I=E/R

ohms law

law that states in a closed loop the applied voltage is equal to the sum of all the voltage drops in the circuit

kirchhoffs law

Characteristic of a parallel circuit

Voltage is common

Current is divided

has multiple current paths

current will enter a parallel circuit and divide among the branches depending on the amount of in each branch

resistance