# Chapter 5 - Principles of Water Flashcards Preview

## IFSTA Pumping and Aerial Apparatus Driver/Operator Handbook - 3rd Edition > Chapter 5 - Principles of Water > Flashcards

Flashcards in Chapter 5 - Principles of Water Deck (37)
1
Q

For fire protection purposes, ordinary fresh water is considered to weigh ______ or _____.

A
1. 4 lb/cu ft

8. 3 lb/gal

2
Q

At ____, water converted to steam occupies approximately ____ times its original volume.

A

212*F

1,700

3
Q

The speed at which fluid travels through a hose or pipe is determined by the _______ upon that fluid as well as the ____ of the orifice through which it is flowing

A

Pressure

Size

4
Q

First Principle of Water

A

Fluid pressure is perpendicular to any surface on which it acts

5
Q

Second Principle of Water

A

Fluid pressure at a point in fluid at rest is the same intensity in all directions

6
Q

Third Principle of Water

A

Pressure applied to a confined fluid is transmitted equally in all directions.

7
Q

Fourth Principle of Water

A

The pressure on a liquid in an open vessel is proportional to its depth.

8
Q

Fifth Principle of Water

A

The pressure of a liquid in an open vessel is proportional to the density of the liquid

9
Q

Sixth Principle of Water

A

The pressure of a liquid at the bottom of a vessel is independent of the shape of the vessel.

10
Q

Atmospheric pressure at sea level is ___ psi, which is considered standard atmospheric pressure.

A

14.7 psi

11
Q

Any pressure less than atmospheric pressure is called _____, and absolute zero pressure is called a _____________.

A

Vacuum

Perfect Vacuum

12
Q

In the fire service, ____ refers to the height of a water supply above the discharge orifice.

A

13
Q

To convert head in feet to head pressure, you must divide the number of feet by _____ (the number of feet that 1 psi will raise one square in column of water).

A

2.304

14
Q

The water flow definition or ________ is stored potential energy available to force water through pipes, fittings, hose, and adapters

A

Static Pressure

15
Q

For every 1-foot increase in elevation, ______ psi is gained.

A

0.434 psi

16
Q

The difference between static pressure and normal operating pressure is ________.

A

The friction caused by water flowing though the pipes, valves, and fittings of the system.

17
Q

_________ is the portion of the total available pressure not used to overcome friction loss or gravity while forcing water through pipes, fittings, hoses, or adapter.

A

Residual Pressure

18
Q

While water is flwoing from a discharge opening, the forward velocity pressure is considered _________.

A

Flow Pressure.

19
Q

_________ refers to the center line of the bump or the bottom of a static water supply source above or below ground level. _______ is the position of an object in relation to sea level.

A

Elevation

Altitude

20
Q

The pressure losses or gains due to gravity are called ____________.

A

Elevation pressure

21
Q

Above sea level, atmospheric pressure decreases approximately ___ psi for every ____ feet.

A

0.5 psi

1,000 feet

22
Q

The fire service definition of ____________ is that part of the total pressure lost while forcing water through piping, fittings, fire hose, and adapters.

A

Friction Loss

23
Q

The following causes friction loss in a fire hose:

A

> Movement of water molecules against each other.
Linings of fire hose/delaminating hose
Couplings
Sharp bends/kinks
Change in hose size or orifice by adapters

24
Q

First Principle of Friction Loss

A

If all other conditions are the same, friction loss caries directly with the length of the hose or pipe.

25
Q

Second Principle of Friction Loss

A

When hoses are the same size, friction loss varies approximately with the square of the increase in the velocity of the flow.

(e.g.)
flow of 200 to 400 gpm (2^2 = 4)
3.2psi @ 200gpm = 12.8psi ub 400gpm. (3.2 x 4 = 12.8)

26
Q

Third Principle of Friction Loss

A

For the same discharge, friction loss varies inversely as the fifth power of the diameter of the hose.

(e. g.)
(2. 5)^5/3^5 = 97.66/243 = 0.4 that of the 2.5 inch. Therefore, the 3-inch hose has 60% less friction loss than the 2.5-inch hose.

27
Q

Fourth Principle of Friction Loss

A

For a given velocity, friction loss is approximately the same, regardless of the pressure on the water.

28
Q

With water being virtually incompressible, a pressure of _____ psi is required to reduce it volume ___ percent.

A

30,000 psi

1%

29
Q

There are three methods of moving water in a system.

A

> Direct Pumping System
Gravity System
Combination System

30
Q

A fire hydrant that received water from only one direction is known as a __________.

A

31
Q

A grid system should consist of the following components:

A

> Primary Feeders
Secondary Feeders
Distributor

32
Q

Large pipes, with relatively widespread spacing, that convey large quantities of water to various points of the system for local distribution to the smaller mains.

A

Primary Feeders

33
Q

Network of intermediate-sized pipes that reinforce the grid within the various loops of the primary feeder system and aid the concentration of the required fire flow at any point.

A

Secondary Feeders

34
Q

Grid arrangement of smaller mains serving individual fire hydrants and blocks of consumers.

A

Distributors

35
Q

The ___________ is the average amount of water used per day based on the total amount of water used in a water distribution system over the period of one year.

A

36
Q

The ____________ is the maximum total amount of water that was used during any 24-hour interval within a 3-year period.

A

Maximum Daily Consumption (MDC)

37
Q

The ____________ is the maximum amount of water used in an 1-hour interval over the course of a day.

A

Peak Hourly Consumption (PHC)