Theory

1.The component that absorbs heat into the refrigerant­ ant is the.      Ans

(A)     metering device.

(B)     condenser

(C)     compressor.

            (D)     evaporator

2.   The heat required to raise 1 pound of water 1deg F is called      Ans

(                                A)     British thermal unit.

(B)     potential energy

(C)     kinetic energy.

(D)     superheat.

3.   The high side of the system includes a(n)     Ans

(A)     metering device.

(B)     evaporator.

(C)     suction line.

(D)     Receiver                                                                                                                                                

4.   Superheat is heat added          Ans

(A)     with the aid of the automatic expansion valve

(B)      after all liquid has been changed to vapor

(C)     for the vaporization of the evaporator

              (D) .  to increase the heat of a substance

5.   In the Fahrenheit scale, boiling water at sea level        Ans

        has a temperature of

                                (A)   144 deg

(B)     970 deg

(C)     212 deg

             (D)        100 deg

6.   The low side of the system includes a(n)       Ans

(A)     receiver

(B)     compressor

(C)     discharge line.

             (D)       evaporator

7.    7.   The heat used to change a liquid to a gas or a vapor is called latent heat of        Ans

(A)   vaporization

(B)    fusion

(C)   condensation

(D)  superheat

8.    8.   A thermometer is said to detect        Ans

(A)  heat of vaporization,

(B)  sensible heat.

(C)  Potential energy.

(D) Hidden heat.

9. Hidden heat in refrigeration work is called        Ans

(A)  Superheat.

(B)  Kinetic heat.

(C)  Sensible heat

(D) Latent heat.

10. Latent heat of vaporization of water is        Ans

(A)  144btu

(B)  212 F

(C)  970 btu

(D) 270 C

11. Which temperature scale uses 212 deg as the boiling point of water?      Ans

(A)  Fahrenheit

(B)  Celsius

(C)  Kelvin

(D) Rankin

12. Zero gauge pressure equals an absolute pressure of      Ans

(A)  7.54

(B)  25.0

(C)  17.4

(D) 14.7

13. The heat required to melt 1 pound of ice a 32 to water at 32 is equal to       Ans

(A)  144 btu

(B)  970 btu

(C)  244 btu

(D) 1114 btu

14 The latent heat of fusion in water is        Ans

(A)  970 btu per lb.

(B)  470 btu per lb.

(C)  144 btu per lb.

(D) 244 btu per lb.

15. What is another word for latent heat?       Ans

(A)  Hidden heat

(B)  Absolute heat

(C)  Sensible heat

(D) Specific heat.

16. Heat added to a gas above the saturation temperature is called       Ans

(A)  specific heat.

(B)  Potential energy.

(C)  Superheat.

(D) All of the above.  

17.  The latent heat used to change a liquid to a gas or vapor is called the latent heat of     Ans

                          (A)        condensation.

                          (B)        fusion.

                          (C)        vaporization.

                          (D)        temperature.

18.                Convection is the process by which      Ans

                          (A) heat moves through gases and liquids.

                          (B) transfer of heat occurs by direct contact.

                          (C) heat gives up to the surrounding air

19.   Conduction is the transfer of       Ans 

               (A)    heat by means of movement.

(B)    heat by direct contact between two objects.

(C)    heat by means of radiation of the sun.

(D)    molecules in motion around a substance

20.   Saturated vapor is      Ans

                    (A)    heat that can be sensed.

(B)    the number of  btu required to change state of an object.

(C)    a substance that has just turned into a vapor.

(D)    all of the above.