#### a/c unit 8

They can vary from time to time based on when and where they were taken

How does atmospheric pressure affect a gauge pressure reading?

A substance that deforms and flows under pressure

What is fluid?

Force per unit area. A comparative measurement that compares force pushing on a surface to the area supporting the force

what is pressure?

The weight of air creating pressure on the earth's surface

What creates atmospheric pressure?

Absolute pressure is real pressure. Absolute pressure is always 0. Gauge pressure is calibrated to 0 to match atmospheric pressure

What is the difference between absolute pressure and gauge pressure?

Elevation of location and Weather (temperature and humidity) higher temperature and higher relative humidity both produce lower atmospheric pressure because it causes the air to expand, reducing its density and weight, which reduces the atmospheric pressu

What caused atmospheric pressure to change?

Barometric pressure is the current atmospheric pressure at a specific location

What is the relationship between atmospheric pressure and barometric pressure?

13 psia (26/2 = 13)

Convert a barometric pressure reading of 26" Hg to pisa.

85.3 psig (psia - 14.7)

Convert a chart reading 100 psia to the reading you would see in gauge pressure.

79.9 psia (psig + 14.7)

The reading on a low side pressure gauge is 65 psig. What is the absolute pressure?

5 psia (30 - 20 = 10) (10/2 = 5)

Convert a reading of 20" Hg vacuum to psia.

Vacuum is any pressure less than atmospheric pressure. It is measured using mercury columns. Mercury columns measure how much pressure has been removed

Define vacuum and tell how it is measured.

Fluids produce force in all directions

What causes fluid pressure?

6.495 psi (.433 x 15)

What is the pressure in psi required to lift water 15 ft.?

Difference in fluid level from one side to the other

Explain how a simple open arm manometer measures pressure.

The total pressure of a mixture of gases is equal to the sum of their individual pressures
(the total pressure of a mixture of gases can be determined by adding each of the individual gas pressures)

Briefly summarize Dalton's law.

Psi. 15 psi = 100 kPa

Which is a larger unit of pressure: 1 kPa or 1 psi?

The molecules have enough attraction for each other that removing heat from them will cause them to condense to a liquid (gas changes state at the saturation point)

Why do saturated gases not follow the ideal gas law?

Gas pressure is exerted uniformly everywhere on its container

Explain Pascal's law.

fred flintstone

mr ray has a striking resemblence to what famous caveman?