Hvac unit 5 introduction to electricity

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1 watt is equal to blank

3.41 BTUs

What is 1 watt equivalent to

3.41 BTUs 3413 kilowatts

1 kilowatt equals blank BTUs

3.412 btu

A circuit has 120 volts 30 ohms what is I

4 amps

What is 1 amp equivalent to

1000 milliamps 1 million microamps

What is 1 voltage equivalent to

1000 millivolts 1 million microvolts

What is 1 kilohm equivalent to

1000 ohms

What is 1 kilovolt equal to

1000 volt

A resistance of 200 Holmes and 50 amps produces how many volts

10000

More people have been killed by contact with

120 volt AC

The nominal supply voltage of a safety control circuit shall not exceed blank volts

120 volts

At what volt has the majority of fatalities.

120 volts ac as little as 42 volts DC can be lethal.

How many inches of wire should be left for making joints or for the connection to receptacles

6 inches should be left at each outlet for making joint or for the connection to receptacles

What is electromagnetic induction

If a conductor is moved across the magnetic field as indicated voltage is generated in that conductor

Define electromagnetic induction

If a conductor is moved across the magnetic field as indicated voltage is generated in that conductor.

Define thermal electricity

If heat is applied to two different metals joined together

In a series circuit can there be more than one path for the current to flow

In a series circuit there is only 1 path of current to flow.

When using a meter to measure voltage how mustuch the voltmeter be connected into the circuit

In parallel to the circuit

When using a amp meter to measure current how much the ammeter be connected into the circuit

In series with the circuit

Name all electrical sources which must be made in operable and what is this state called.

Including electrical pneumatic hydraulic gravitational must be made inoperable this is often called zero mechanical state

Black wire sometimes red or blue

Insulated live or hot conductors

Generally electricity arrives at a receptacle inside a two conductor cable and includes a ground wire. Generally what are the white and natural gray

Insulated neutral conductors

What is a VOM or multimeter used for

Its functions as a voltmeter an amp meter and an ohmmeter

What's the purpose of a running capacitor

Keeps voltage source constant

What is the fundamental law that governs the way charged particles behave

Like charges repel unlike charges attract

How is thermal electricity measured

Measure millivolts DC

how is thermal electricity measured

Millivolts

Electrons charge is considered to be blank charge

Negative

In which direction in a conductor does DC always flow

Negative to positive

Atoms are made up of three parts what are they

Neutrons protons and electrons

Can you take a victim who is still connected to the electric power

Never touch a victim who is still connected to the electric power.

What type of meter is used to measure resistance or continuity

Ohmmeter

What is 1000 amp equal to or equivalent to

One kilo ampere

Which letter represents power and how is it measured

P measured in watts

In most jurisdictions blank are required for all electrical work to be performed

Permits

Pressure is applied to certain crystal materials what is this called

Piezoelectricity such as gas barbecues

Define power and work

Power is the rate at which work is done

In the absence of other instructions what five steps must be followed to rescue a shock victim

Protect yourself.Dp do not touch the energies victim .Free the victim from electrical contact Apply CPR. Call 911 Continue CPR until a medical authority tells you to stop

What happens to resistance when the skin is wet or salty

Resistance drops

When skin is wet or salty it blank blank to several hundred from several thousand ohms

Resistance drops

How does the step down transformer differ from the single phase transformer operation

Secondary winding has fewer turns than the primary winding so the secondary voltage is less than the primary voltage also the secondary current is greater than the primary current windings primary and secondary will be proportionate. Check answer.

The strength of the forces of attraction and repulsion depends on A the amount of charge on each subject B the square of the distance between the object or C both of the above

See both of the above

What is the definition of Ohm's law

The current flowing in electrical circuit is directly proportional to the applied voltage

In a parallel circuit what voltage is applied across each branch

The entire sourceStudying Hvac unit 5 introduction to electricity on Quizlet: https://quizlet.com/105226579/hvac-unit-5-introduction-to-electricity-flash-cards/ voltage applied voltage

What is formed when several thermocouples are joined together

Thermopile

What are the laws of a parallel circuit

Voltage is constant across each branch in the circuit ET=E1=E2 check answer amperage is the sum of the current flowing through each branch. Resistance RT is smaller than the smallest resistor in the circuit.

Electric current

When electrons are made to move in the same direction they produce an electric current.p

Describe photo electricity

When light strikes certain materials such as potassium and sodium the energy from the light causes the Adam to release electrons this is called the photoelectric effect UV an infrared

What is the definition of electromagnetism

Whenever current flows in a conductor a magnetic field forms around the conductor also if a conductor is moved within a magnetic field of voltage will be induced and current will flow in the conductor

The flow of electric current carries energy that can perform blank

Work

are the terminals on receptacles usually identified to indicate which conductor is to be connected for example the neutral wire terminal is identified by a metallic coding or is made of metal that is substantially white silver in color or is Mark W or white adjacent to the terminal the ground terminal screwing head nut or clamp is colored green

Yes

Does the load usually have resistance in the electrical circuit

Yes the load usually has resistance.

True or false all electric power for the heating unit and associated equipment operating in connection with it shall be obtained from a double branch circuit that shall be used for other purposes

False

Name three circuit protective devices

Fuses circuit breakers thermal and magnetic overloads

Green

Green wire only for ground conductors

What type of charge is associated with the following. Fewer electrons than protons fewer protons than electron and the same amount.lectrns and protons.

Has a positive charge has a negative charge is neutral

When electricity flows in a current it can produce these useful effects name three

Heat magnetism chemical changes

Applying enough force to remove the electrons can be done by using for example

Heat thermal electricity magnetism electromagnetism chemicals electrochemistry pressure p0 electricity light photoelectricity

What is one microhm equal to

0.000001 homes

What is 1 mlliohm equal to

0.001 ohms

What is 1 mega ohm equal

1 million ohms

What is 1 megabytes equal to

1 million volts

Branch circuits in dwelling units shall not have a voltage exceeding blank to ground with the exception of a BNC rule 2 - 110 circuit voltage to ground dwelling units

150 volts

A circuit has 90 volts 20 amps what is R

4.5 ohms

How many milli amps can kill you?

50 mA

What is meant by strength of a coil magnetic field

A closely round coil create the stronger magnetic field

What type of circuits allow current to flow through more than one complete piath

A parallel circuit

What is electrochemistry

A voltaic cell is made by immersing two different metal electrodes in a chemical solution called electrolyte

Who responds better to artificial respiration a victim of high voltage shock or low voltage shock

High voltage

What is defined as high voltage

Above 750 volt

Blank on the other hand regularly reverses direction and occurs when the polarity of each end of the conductor is reversed which is always the case with most current

Ac alternating current

What does a load do.

Alowed use electrical energy to do use for work such as producing motion light or sound or to provide heating

In North America electrical energy is produced and transmitted as blank blank with a frequency of blank hurts

Alternating current flows in one direction for one 120th of a second and then in the other direction for one 120th of a second 60 Hertz

Factors affecting electric shock blank blank blank blank blank blank

Amount and path of current type of voltage AC or DC value of voltage length of time the body is energized condition of the skin area of the skin

What are the laws of a series circuit

Amperage is consistent resistance is the sum of all loads in the circuit. RT= R1+R2+R3 Volts in a series circuit ET Total the sun of the voltage drop across each load in the circuit.

What does a simple electrics circuit consist of

An energy source conductor and load.

Which victims respond better to CPR high or low voltage

High voltage victims

Why must an ohmmeter never be connected into a live circuit

Could damage ohlmeter an batteries could explode.

How does a closely wound coil affect ghd magnetic firld

Creates a stronger magnetic field.

What are the three all ohms law equations.

I=EoverR or R=E over I or E=I XR

When current flows in a constant direction it is called blank

Direct current DC

which current only flows in one direction

Direct current DC

When using the olm meter what must be done before you can use this meter

Disconnect circuit power and discharge all high voltage capacitors before testing resistance continuity diodes or capacitance.

When electrons are made to move in the same direction they produce blank blank

Electric current

What produces electricity by electromagnetism

Electric generator

Two different metal electrodes in a chemical solution is called blank

Electrolyte

Electric generator produces electricity by blank

Electromagnetism

How do you calculate values in a series paralell circuit?

Total circuit resistance total line currant voltage drops across the series componamts branch current flow? I

True or false high voltage electricity can arc or jump across an air gap from one point to another if the voltage between the two points is strong enough for this reason personnel must remain well clear of high-voltage equipment

True

True or false thermocouples are often use a thermometer to detect and measure temperature the current produced by a thermocouple is enough to hold in a small electro magnet within a gas valve indicating the presence or absence of a pilot flame

True

True or false starting capacitors ratings are from 75 to 600 microfarads and with voltage ratings of 110 volts to 3330 volt

True it takes the charge wacks the fan to start working


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