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Question 1

If all other factors are held constant, volume of dry air (gas) decreases?
A) In direct proportion to an increase in its pressure B) When its pressure is decreased C) In direct proportion to an increase in its temperature D)As the square of the rate of the temperature increases

Answer 1

A) In direct proportion to an increase in its pressure page 3

Question 2

Absolute pressure is equal to? A) 14.7 psig B) Gauge pressure less 14.7 C) Gauge pressure plus 14.7 D) Gauge pressure plus altitude

Answer 2

C) Gauge pressure plus 14.7 page 3

Question 3

If 500 cu. inches of gas under a pressure of 15 psi a compressed to 20 cu. inches what is the new pressure? A) 2 psia

B) 375 psia C) 667 psia D) None of the above

Answer 3

B) 375 psia Use formula P2/P1 = U1/U2 P2/15psi = 500in3/20in3 P2=375psi page 3 & 5

Question 4

The quantity and pressure of air discharged from a centrifugal fan depends on the? A) Size of the fan rotor
B) Speed of the fan rotor C) Density of the air D) All of the above

Answer 4

D) All of the above page 9

Question 5

Increasing the speed of an unbalanced shaft will?
A) Move the center of gravity further from the axis of rotation there by improving the balance B) Move the axis of rotation closer to the center of gravity C) Move the center of gravity further from the axis of rotation thereby increasing the unbalance D) Will have no affect on the location of the center of gravity

Answer 5

C) Move the center of gravity further from the axis of rotation thereby increasing the unbalance page 15

Question 6

The temperature at which molecules of water vapor begin to condense upon the surface of objects as air is cooled is called the? (The point where water forms on surfaces when there is a variance in pressure and temperature is called?) A) Saturation
B) Boiling point
C) Dew point D) Relative Humidity

Answer 6

C) Dew point page 31

Question 7

Which of the following conditions would not normally contribute to reciprocating air compressor explosion? A) Excessive recompression B) Excessive water accumulation C) Excessive lubrication D) Excessive compressed air demands

Answer 7

D) Excessive compressed air demands page 27

Question 8

Large reciprocating air compressors are generally unloaded while starting and stopping to? A) Prevent explosions B) Prevent excessive pressures from building up in receivers C) Prevent moisture carry-over into discharge lines D) Reduce the starting torque and permit more gradual stopping

Answer 8

D) Reduce the starting torque and permit more gradual stopping page 25

Question 9

High outlet compressed air temperatures could be caused by all of the following except? A) Faulty valves and recompression B) Fouled cooling surfaces
C) Low oil level
D) High inlet air temperatures

Answer 9

C) Low oil level page 30 & 31

Question 10

Air receivers are installed on all reciprocating air compressors to A) Dampen pressure waves B) Reduce pressure drops C) Remove moisture or sludge D) All of these

Answer 10

D) All of these page 31