water Supply 2

Question 1

At high flows, most of what is commonly called friction loss is due to which of the following?
A. friction between the water and the hose lining
B. turbulence at the hose couplings
C. turbulence within the water flow
D- gently curving bends in the hose

Answer 1

C. turbulence within the water flow

Question 2

Which of the following factors does not affect the water supply capability of a given layout? 
A. the capacity of the pump 
B. the capacity of the hose 
C. the capacity of the water source 
D. the available staffing

Answer 2

D. the available staffing

Question 3

The minimum incoming pressure that a fire pump should receive is: 
A. 5 Psi 
B. 10 psi 
C. 25 psi 
D. 150 Psi

Answer 3

B. 10

Question 4

Where long distances or large flows are required of a relay operation, which choice doesn’t solve the water delivery problem?
A. changing the size of the discharge nozzle
B. laying multiple supply lines
C. using large diameter supply lines
D. using a larger capacity pumper at the source

Answer 4

A. changing the size of the discharge nozzle

Question 5

What are some of the advantages of a telescoping platform over an aerial ladder for elevated master stream use?

1. greater tip-loading capacity
2. greater discharge capacity
3. greater range of motion of the stream
4. higher elevation
5. the ability to reach over obstructions, such as wires, in front of a fire building

Answer 5

B. 1, 2, and 3 only

Question 6

1, By dividing the flow of water from one line into two similarly sized lines, the friction loss is reduced to what percentage range of the loss for a single line? 
A. 25-35% 
B. 45-55% 
C. 60-70% 
D. 75-85%

Answer 6

A. 25-35%

Question 7

One cubic foot of water weighs most nearly: 
A. 8.5lb 
B. 52lb 
C. 62lb 
D. 72lb

Answer 7

C. 62lb

Question 8

Elevation pressure loss when pumping to an upper floor can be estimated at how many psi per floor, given 10 ft per story?
A. 0.434 psi . 
B, 2 psi 
C. 5 psi 
D. IO psi

Answer 8

C. 5 psi

Question 9

maximum height from which it is theoretically possible to draft water using a centrifugal fire pump is approximately: 
A. 14.7 ft 
B. 20 ft 
C. 25 ft 
D. 33 ft

Answer 9

D. 33 ft

Question 10

What effect would tripling the length of a hoseline have on the total friction loss if the flow remained the same? A. None
B. one-third the loss
C. triple the loss
D. nine times the loss

Answer 10

C. triple the loss

Question 11

What effect does increasing the diameter of a hoseline have on the flow if the friction loss per foot remained constant? 
A. none 
B. flowing 
C. increased flow 
D. reduced flow

Answer 11

B. flowing

Question 12

Of the following types of water pressure, which is of most use to firefighters considering a hydrant-to-fire hose stretch?
A. static 
B. flowing 
C. residual 
p. head

Answer 12

B. flowing

Question 13

“Positive pumping through large-diameter hose is the most efficient use of hose, pump, and aerial device.” This statement is:
A. correct
B. correct, if pump discharge is the same as nozzle rating
C. correct, if pump discharge rating is less than nozzle rating
D. incorrect

Answer 13

D. incorrect

Question 14

Which of the following hydraulic principles is incorrectly stated?
A. Regardless of the diameter of a hose, the more water flowing through it, the higher the friction loss will be.
B. Regardless of the length of a hoseline, at a given flow, the friction loss remains the same.
C. By increasing the discharge rating of a pumper, more water can be delivered at the same pump discharge pressure.
D. Regardless of the flow, by increasing hose diameter, the same amount of water can be moved farther with the same amount of

Answer 14

B. Regardless of the length of a hoseline, at a given flow, the friction loss remains the same.

Question 15

Applying hydraulic knowledge to water supply problems allows firefighters to correctly supply hose streams. Which statement below is least correct regarding hydraulics?
A. By increasing the diameter of a hoseline, more water can be delivered at the same pump discharge pressure.
B. By increasing the length of a hoseline, more water can be delivered at the same pump discharge pressure.
C. By increasing the discharge rating of a pumper, more water can be delivered at the same pump discharge pressure.
D. By increasing the discharge rating of a pumper, more water can be delivered at a higher pump discharge pressure.

Answer 15

B. By increasing the length of a hoseline, more water can be delivered at the same pump discharge pressure.