NATE Exam- Core Test Refresher -questions with correct answers, Exams of Nursing

Download NATE Exam- Core Test Refresher -questions with correct answers and more Exams Nursing in PDF only on Docsity! NATE Exam- Core Test Refresher - questions with correct answers Calculate the air volume based upon these conditions: 90,000 BTUH output Return air temperature: 70F Supply air temperature: 110F a. 1,158 CFM b. 1,500 CFM c. 1,800 CFM d. 2,083 CFM - ANSWER: d (2,083 CFM) When measuring CFM using temperature rise method, the furnace blower motor speed should be in: a. Continuous fan speed b. Cool mode speed c. Heat mode speed - ANSWER: b (Cool mode speed) If a single phase electric heat section is supplied with 225 volts and is drawing 45 AMPS, the BTUH output of the heat section is: a. 34,500 BTUH b. 25,000 BTUH c. 45,000 BTUH - ANSWER: a (34,500 BTUH) When measuring temperature rise, take the supply air temperature directly in line with the heater section of the air handler: a. True b. False - ANSWER: b (False) When measuring external static pressure, the high port of the pressure gauge should be placed in the duct system to sense: a. Supply air pressure b. Return air pressure - ANSWER: a (Supply air pressure) When the external static pressure rises, the delivered air volume will: a. Increase b. Decrease - ANSWER: b (Decrease) When measuring external static pressure on a gas furnace that utilizes an evaporator coil, the supply air static pressure should be taken at: a. The inlet to the evaporator b. The outlet of the evaporator - ANSWER: a (The inlet to the evaporator) The pressure gauge used to sense external static pressure in a residential duct system should have a pressure range scale of: a. 0-1" water column b. 0-5" water column c. 0-10" water column - ANSWER: a (0-1" water column) d. Enthalpy - ANSWER: d (Enthalpy) On a Psychrometric chart, the ____ temperature is listed at the bottom of the chart. a. wet bulb b. latent c. dry bulb d. dew point - ANSWER: c (dry bulb) The formula for Ohms Law is: a. E = I x R b. E = T x R c. E = P x I d. E = P x R - ANSWER: a (E = I x R) The correct formula for determining Resistance using Ohms Law is: a. R = R/E b. R = E x I c. R = I/R d. R = E/I - ANSWER: d (R = E/I) The best conductor of electrical current between these two choices is: a. A large diameter wire b. A small diameter wire - ANSWER: a (A Large diameter wire) A simple series circuit has a DC voltage source. The voltage source is 9 volts. The circuit has a resistor rated at 18 Ohms. Using Ohms Law, determine the electrical current flowing in the circuit. a. 18 Amps b. 9 Amps c. 2 Amps d. 0.5 Amps - ANSWER: d (0.5 Amps) A simple series circuit has a DC voltage source. The voltage source is 5 volts. The current flowing in the circuit is 0.2 Amps. Using Ohms Law, determine the circuit resistance. a. 25 Ohms b. 10 Ohms c. 55 Ohms d. 5.5 Ohms - ANSWER: a (25 Ohms) If two resistors are placed in parallel configuration, the total resistance of the resistance in the electrical circuit would: a. Decrease b. Increase - ANSWER: a (Decrease) Ohms Law can be used to determine current flow in an inductive circuit. a. True b. False - ANSWER: b (False) In an inductive circuit current ____ voltage. a. Leads b. Lags - ANSWER: b (Lags) The best power factor is ____. a. 1 b. 2 c. 5 d. 10 - ANSWER: a (1) A capacitor will correct Power Factor. a. True b. False - ANSWER: a (True) The correct formula for calculating Watts Law in a resistive circuit is: a. Power = Current x Resistance b. Power = Volts x Amps - ANSWER: b (Power = Volts x Amps) Capacitive and Inductive circuits use the same Watts Law formula as resistive circuits. a. True b. False - ANSWER: b (False) A Kilowatt equals: a. 100,000 Watts b. 1,000 Watts c. 10,000 Watts d. 7,200 RF - ANSWER: c (3,600 RF) When a blower wheel comes up to speed, the current draw of the blower motor will ____. a. Rise b. Fall c. Not change - ANSWER: b (Fall) It is recommended that most motors operate within the Service Factor for best reliability. a. True b. False - ANSWER: b (False) Air volume delivered by a blower assembly can be increased by increasing motor horsepower. a. True b. False - ANSWER: b (False) Thermisters are tested with a: a. Tachometer b. Voltmeter c. Amp meter d. Ohm meter - ANSWER: d (Ohm meter) Thermisters can have negative or positive coefficients. a. True b. False - ANSWER: a (True) A diode will conduct current in only 1 direction. a. True b. False - ANSWER: a (True) A Triac can conduct current in both directions. a. True b. False - ANSWER: a (True) A Silicon Controlled Rectifier (SCR) is a slow switch that can handle high current. a. True b. False - ANSWER: b (False) A potential relay is a normally open relay. a. True b. False - ANSWER: b (False) Potential relays switch a start capacitor out of the compressor start circuit after about a minute of compressor operation. a. True b. False - ANSWER: b (False) A potential relay electrical solenoid is energized by the Start Winding Back EMF from the compressor. a. True b. False - ANSWER: a (True) 187 volt potential can be obtained if the line transformer is wired in this configuration: a. Delta b. Y - ANSWER: a (Delta) An R-22 system is operating with 85 PSIG suction pressure. The temperature of the suction line is 75F, the suction vapor superheat level in this example is: a. 160F b. 10F c. 25F d. 0F - ANSWER: c (25F) If a system is operating with low pressure and the measured suction vapor superheat is higher than normal, the likely cause is: a. Not enough refrigerant in the evaporator b. A dirty filter - ANSWER: a (Not enough refrigerant in the evaporator) A system is operating with lower than normal liquid subcooling. One thing that may correct the problem is: a. Add charge b. Recover charge c. Try a different refrigerant - ANSWER: a (Add charge)