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50 Cards in this Set
- Front
- Back
What is the Formula for calculating power in an electric circuit?
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P=I x E
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How much airflow is required for a 3 Ton system?
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1200 CFM
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What is the Total Resistance of a Circuit that has 3 30 Ohm Resisters in Parallel?
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10 OHMS
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If Guage Pressure is 30 PSI What is Absolute Pressure?
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44.7 PSIG
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Enthalpy includes both ___________ and _____________ Heat Energy?
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Sensible and Latent
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The Theoretical Temperature at which all molecular motion stops is called ______________?
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Absolute Zero
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An Ampere is defined as Current equal to ?
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One Coulomb per Second
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What is the symbol for Voltage?
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E
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How much current does a 100 Watt lighbulb draw at 120 Volts?
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.83 Amps
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The Sensitivity of a Voltmeter is Measure in ?
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Ohms per Volt
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Name 2 types of Ice Machines
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Cubed and Flaked
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How much ice does a commercial Ice machine produce in 24 Hours?
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50 to 5000 LBS
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What further categories are Ice machines divided into?
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Self-contained and Modular
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Is Ice considered a food product?
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Yes
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Ice machines most frequently require maintenance within what system?
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Water System
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What is "Stack Effect"?
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The tendancy of Air to Flow in and out of a building caused by lighter, rising warm air transfering with colder, denser air to and from inside and out.
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How does a Heat Anticipator Work?
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A Heat Anticipator causes the thermostat to sense a temperature higher then the actual room temperature
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How are low voltage contacts of a thermostat usually activated?
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By the movement of Bi-Metal
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Is the Heat Anticipator powered during the heating cycle or the OFF cycle?
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Heating
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Name 3 Lubrication problems that can cause compressor failures?
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Insufficient Oil, Loss of oil in the crankcase, Failure of the oil pump.
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Most workplace injuries can be avoided by practicing
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Good judgement and Caution
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List 3 types of eye protection that should be worn on the job.
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Goggles, Face Shields, and Spectacles with Side Shields
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What steps should be take following a workplace accident?
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1) Report accident to employer or supervisor
2) Notify affected parties 3) Current codes and regulations should be followed. 4) Serious accident sites should remain undisturbed |
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Refrigerant cylinders should be transported in what position.
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Upright, secured
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Name 4 categories of Hazerdous atmospheres.
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Flammable, Toxic, Irritant, Asphyxiating
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Asphyxiation can occur when the oxygen supply is depleted by what two occurances?
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Consumption and Displacement
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List 4 general types of hazards associated with electricity.
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Burn, Blast,Shock, Related (Falling off ladder)
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When using electric power tools you must make sure they are _____ or ____.
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Grounded or Double Insulated
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When is it permissible to improperly size fuses?
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Never
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An electric shock of as little as _____ can cause the victim the inability to let go.
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5ma
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How does a ground fault circuit interrupter work?
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It detects an imbalance between line and neutral current and disconnects the source power.
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What classification is given to Electrical Fires?
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Class C
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What is the first step of the Lockout procedure?
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Notify everyone concerned that you will be working on the equipment.
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Heat is a form of?
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Kinetic Energy
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Stored energy is called __________ energy.
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Potential
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Heat transfers from ______ to ______?
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Hot to Cold
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What type of heat is associated with a change of state?
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Latent Heat
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What type of heat can be measured with a typical thermometer?
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Sensible
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THe amount of heat required to raise the temperature of 1 lb of a specific substance 1 degree Farenheit is called __________.
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Specific Heat
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Define cold.
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Reduced amount of Heat
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The latent heat of fusion is the amount of energy required to change 1 lb of a substance from the ________ phase to the ________ phase without changing the temperature.
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Solid to Liquid
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The amount of energy required to change 1 lb of a substance from the liquid phase to the vapor phase without changing the temperature is called the ___________ of the substance.
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Latent Heat of Vaporization
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When the liquid and vapor phases of a substance exist together, and no more liquid can vaporize without adding more energy. The vapor is said to be _______________.
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Saturated
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When a vapor is heated to a temperature higher then its saturation point, both the added heat and the temperature difference is called ________.
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Superheat
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The process of molecules escaping from the surface of a liquid is called
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Evaporation
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A capacitor is made up of 2 metal plates separated by a?
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Dielectric
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Define Capacitance
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Opposition to DC Current Flow
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How can a capacitor's value be increased?
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Increase the plate size, change the dielectric, distance between plate or add capacitance in parallel.
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What determines the safe working voltage of a capacitor?
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The Voltage Rating
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A start capacitor usually has a ________ value of capacitance and a ________ voltage rating than a run capacitor.
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Higher, Lower Opposite is true of Run Capacitors
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