Hydraulics and Water Supply Flashcards
(263 cards)
Water is most useful for FF when it exists in its
Liquid state
Water exists in its liquid state between what temps
32 and 212 degrees F
Water is _____ in its liquid state
Incompressible
1 cubic foot of water contains
7.48 gallons in a liquid state
Waters density is measured in
pounds per cubic foot
Water is most and least dense in which states
Dense - freezing point
Least dense - boiling point
How many pounds does a gallon water weigh
8.34 pounds
What are the primary ways in which water extinguishes fire
Cooling and smothering
What 2 laws of physics are important for firefighting
Law of specific heat
Law of latent heat of vaporization
All substances have a given capacity to absorb heat explains what
Law of specific heat
Amounts of heat transfer are measured in
BTU or Joules
This is the amount of heat required to raise the temp of 1 pound of water 1 degree F
BTU
The ratio between the amount of heat needed to raise temp of specified quantity and amount of heat needed to raise temp of identical by same number of degrees
Specific heat of any substance
Water absorbs heat _____ more effectively than what
500 times, Carbon dioxide
The amount of heat that water can absorb when it changes from a liquid to a vapor is referred to as
Latent heat of vaporization
The fire service has commonly used a ratio of ____ for water to steam conversion
1:1,700
Waters considerable amount of surface tension limits what
Its ability to soak or penetrate combustibles
The study of water at rest and the science behind that study is called
Hydrostatics
The pressure at a point in a liquid is applied equally in every direction is known as
Pascal’s law
Function of a given force applied over a specific area
Pressure
The pressure of a liquid in an open container is what
Proportional to its depth
Pressure created by a static liquid is equal to what
Weight x height
Pressure expressed in units of feet of water instead of pounds per square in
Head
The amount of pressure created by the height of the column of water
Head pressure