PHEP 1 Matter Flashcards
Which of the four elements listed as it is the lightest per unit volume?
Calcium
Which of the four elements listed as the lightest per atomic weight?
Carbon
Water is…
A compound
When two or more atoms combine chemically, the particle that’s formed is a ___?
molecule
A compound is formed when the atoms of two or more elements become_____?
Chemically bonded
Our air (or atmosphere) is composed by volume of ____ and ____
21% oxygen, 79% nitrogen
Atmospheric pressure at sea level is normally considered to be approximately
14.7 psi
When molecules are tightly bound they are in a
Solid state
Liquids offer a high resistance to any force tending to change their
Volume
A pound is a unit of
Force
A temperature reading of 59°F is equivalent to
15 degrees C
A temperature reading of 85°C is equivalent to
185°F
Density is a ratio between mass and
Volume
When the temperature of a substance increases, or the pressure is reduced, the substance…
Expands and becomes less dense
If an object weighs 210 pounds and the volume is 3.5 ft.³ what is the objects density?
60 ft.³
Water has a density of 62.4 pounds per feet cubed. The volume of 1000 pounds of water is
16 ft.³
What can be used to find the weight of objects which cannot be waited on scales
Specific gravity
A piece of concrete weighs 400 pounds in air and 350 pounds in water. What is its specific gravity
8
Specific weight most nearly means
Density
Atmospheric pressure is
Greater at sea level
The term viscosity most nearly means
Resistance to physical change
The pressure upward at any given point in a liquid is ____ the downward pressure at that point
The same as
What is the pressure on the bottom of a discharge line at 200 feet deep?
12,480 lbs/ft^2
Hey slanting penstock 2000 feet long conveys water from a reservoir to a turbine 800 feet below sea level of the reservoir. Pressure at the turbine is…
49,920 lbs/ft^2
What is the force on the bottom of a tank 6’ x 8’ x 12’ failed to a depth of 3 feet with water
8,985.6 lbs
Force = area x height x density
(What is the force on the bottom of a tank 6’ x 8’ x 12’ failed to a depth of 3 feet with water)
If the tank in this problem is filled to the top with oil who’s density is 72 pounds per cubic foot what pressure is being exerted on one square inch of the base?
6 lbs/sq in.
Height x specific weight divided by 144
To convert gauge pressure to absolute pressure at sea level conditions
Add 14.7 (assuming pressure of atmosphere)
The pressure against the large piston in a confined space is
Proportional to the area on a small piston
Fluid pressure might be expressed properly by?
Lbs/in^2
The forces that are required to move fluid through a siphon are?
Friction head and static head
What are the formulas for converting Fahrenheit to Celsius
C= 5/9 (F-32
F= 9/5 (C) + 32
Formula for density (specific weight)
D= total weight/ volume, answer is cubed
Formula for specific gravity with objects on air to objects in water
Specific gravity = weight in air/ weight in air - weight in water
What is a cubic ft of water
62.4 lb
Formula for pressure per sq inch
= (Height in ft x specific weight per cubic ft) /144
