Ch. 6 What is Water?

What produces movement of fluid?

Pressure Pg- 141

A 250 foot hose is attached to a hydrant. A nozzle with a closed bale is attached to the end of the hose. Pressure gauges are inserted at the couplings 50 feet and 200 feet from the hydrant. The hydrant discharge is open but the bale is closed, so that the hose is charged but no water is flowing? Pressure will be __________ at both gauges

Pressure will be the same at both gauges

Which part of a grid system consists of large, high capacity pipes?

Primary feeders

A dead-end hydrant is one that __________.

Receives water from only One Direction

At a given flow velocity, as pressure varies, friction loss __________.

Remains about the same

The remaining pressure that is left over after forcing water through pipes, fittings and hose is __________ pressure.

Residual

Which part of a grid system consists of intermediate capacity pipes that reinforce the high capacity grid?

Secondary feeders

What is a commonly found feature of privately owned water supply systems that is unusual in municipal systems?

Separate piping for the fire protection water supply.

What is the pressure measured at a hydrant with no water flowing?

Static pressure

What is the stored potential energy that is available to push water through pipes, fittings, hose, etc?

Static pressure

What does vaporization of water produce?

Steam

Water's rate of heat absorption is increased the most by increasing the __________ of the water.

Surface area

What does the latent heat of vaporization measure?

The amount of heat needed to convert a substance from a liquid to a vapor.

What is a BTU?

The amount of heat needed to raise the temperature of one pound of water one degree.

What does specific heat measure?

The heat absorbing Capability of a substance

When used in the context of hydraulics, what is "head"?

The height of a water supply above its discharge.

A 250 foot hose is attached to the hydrant. A nozzle with a bale is attached to the end of the hose. Pressure gauges are inserted at the couplings 50 feet and 200 feet from the hydrant. The hydrant discharge is opened and the bale is opened about halfway, so that there is a moderate flow of water. Pressure will be lowest at the gauge farthest from the hydrant? True or false.

True

3 key measurements engineers consider in water distribution system design are: Peak hourly, Average daily, Maximum daily consumption? True or False

True Not AVERAGE PER CAPITA

All other things being equal, friction loss __________ with the length of a hose.

Varies directly

The speed at which a fluid travels is its __________.

Velocity

What substance has the highest specific heat? Water or sodium bicarbonate?

Water

What is created by suddenly stopping moving water?

Water hammer

Which statement about a combination water supply system is correct?

Water pressure is provided by the use of gravity fed and pumps

To control the flow of the water through distribution piping describes the purpose of a ____________.

Water valve

A hydrant that receives water supply from more than one direction has _________?

circulating feed

As altitude increases, what happens to atmospheric pressure?

it decreases

A column of water that is one inch square at its base and 12 inches tall exerts a pressure at its base of ________ psi.

0.434

Water converted to steam will expand to approximately _____ times its original volume.

1,700

in order to remain in good condition water supply system valves should be operated at least once every________ months.

12 months

Atmospheric pressure at sea level is _____ psi.

14.7

Atmospheric pressure at sea level is ________ PSI.

14.7 PSI

As a practical matter, the minimal elevation at which decreasing atmospheric pressure begins to affect pump performance is about _____ feet.

2,000

A column of mercury in a barometer rises _____ inch(es) for each 1 psi of atmospheric pressure.

2.04

A column of mercury in a barometer rises __________ inches for each 1 PSI of atmospheric pressure.

2.04

At what temperature (In degrees F) does water convert from a liquid to a gas?

212 F

Doubling the diameter of a hose will increase the area of the hose opening approximately _____ times.

4

doubling the diameter of hose will increase the area of the hose opening approximately _______ times?

4

For every 10 feet of head, pressure increases by _________ PSI.

4.33

For every ten feet of head, pressure increases by _____ psi.

4.33

Friction loss in a 3 inch hose is roughly _____% of that in a 2.5 inch hose of the same length.

40

There are _____ principles governing the effects of pressure on fluids.

6

Minimum diameter for hydrant supply lines in residential areas is ______ inches.

6 inches

A cubic foot of water weights about ________ lbs.

62.5 pounds

Minimum diameter for hydrant supply lines in business/ industrial areas is _______ inches.

8 inches

Ordinary fresh water weighs about ________ LBS per gallon.

8.3

Ordinary fresh water weighs about _________ lb per gallon.

8.3 per gallon

Approximately how many btu's are absorbed when one gallon of water is converted into steam?

9,000

Which water valve has a disk that rotates 90 degrees from fully open to the fully closed position?

Butterfly

Which water valve has a disk that rotates 90 degrees from the fully open to the fully closed position?

Butterfly

The weight of water within a container exerts pressure that is ________? A. Parallel to the walls of the container B. Primarily downward C. Perpendicular to the walls of the container D. Parallel to the base of the container

C. Perpendicular to the walls of the container Pg- 142

What is the usual cause of water hammer?

Closing a Valve to suddenly

Placing a nozzle on a hose with an open butt causes friction loss within the hose to __________.

Decrease

As flow velocity decreases, friction loss ________?

Decreases

As flow velocity decreases, friction loss __________.

Decreases

Flow pressure __________ the further away it is measured from its source.

Decreases

The pressure of a liquid in an open container is proportional to its __________.

Depth

Which water system uses pumps to move the water from the supply to the treatment and filtration system?

Direct pumping system

The part of a water supply system that receives water from the pumping station and delivers it throughout the service area is known as the ___________.

Distribution system

Which part of a grid system consists of relatively small lines serving hydrants and groups of users?

Distributors

For a given flow, doubling the length of hose will __________ total friction loss.

Double

What is pressure gain or loss due to elevation?

Elevation pressure

A moving piston is applying pressure to fluid in a closed cylinder. The direction of the pressure in the water is __________.

Equal in all directions

The direction of pressure in a fluid at rest is __________.

Equal in all directions

A moving piston is applying pressure to a fluid in a closed cylinder. The direction of the pressure in the water is ?

Equal in all directions.

What is the pressure measured by inserting a pitot tube in the stream of water flowing from an open hydrant discharge?

FLow pressure

Increasing discharge volume will reduce friction loss? True or false?

False

What is forward velocity pressure of flowing water at a discharge opening?

Flow pressure

What is the reduction in pressure caused by the resistance of water to movement through pipes, appliances, hose, ETC?

Friction los

An OS&Y valve is an example of which type of valve?

Gate valve

Which water system uses pressure provided by a water source at a higher elevation than the distribution system?

Gravity fed

Which water system uses pressure provided by a water source at a higher elevation than the distribution system?

Gravity system

Which water system provides circulating feed from several mains?

Grid system

What is a disadvantage of water as an extinguishing agent?

High surface tension

Friction loss will be reduced by all of the following EXCEPT ONE. CHOOSE THE EXCEPTION.

Increasing discharge volume

Most valves in private fire protection systems are of which type?

Indicating

As flow within a given length of hose doubles, friction loss __________.

Is squared

What shape container will the pressure of a liquid be greatest at the bottom of a container?

It will be the same regardless of the container shape.

Liquids with a specific gravity of less than one are __________

Lighter than water

What is the point of locating valves at frequent intervals within a water system?

Minimizing the area affected when valves must be closed

What is the pressure in a water system during normal consumption demands?

Normal operating pressure

What is the best example of an indicating valve?

Outside stem and yoke.

Which notation indicates a pressure reading that takes into account the effect of atmospheric pressure?

PSIA

Which notation indicates a pressure gauge that does NOT take into account the effect of atmospheric pressure?

PSIG