Calculating air density from a barometer?

In summary, the conversation is about calculating the density of air for a lab report. The ambient temperature and barometer reading are given, along with two correction factors. The person is asking for help in using this information to find the air density and is also curious about the purpose of the correction factors. They mention relevant equations and values for standard sea level conditions. They attempt a solution using the formula ρ=p/(RT), but are unsure how to incorporate the correction factors. They ask for assistance in understanding the use of correction factors and express gratitude for any help.
  • #1
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Homework Statement



Working on a lab report, where we are asked to calculate the density of air.

Ambient Temperature: 19°C
Barometer (mm Hg abs): 765
There were two correction factors: 2.35 and 2.41

How do I use the above information to find the Air Density (kg/m3) ?
What are the correction factors? And, why did we take two correction factors?

Homework Equations


I know that: 1mm Hg = 133 Pa; and μ=1.8*10^-5 Nsm^-2

σ=δ/θ where δ=p_ambient/p_sls and θ=T_ambient/T_sls
We know that:
ρ_sls=1.225 kgm^(-3)
p_sls=760 mm Hg abs
T_sls=288 K (15°C)

Hence:
δ=p_ambient/(1.225 kgm^(-3) )= and θ=T_ambient/(288 K) =
Thus:
σ=δ/θ= δ/θ=

The Attempt at a Solution



Using ρ=p/(RT)

where T=292.15 K, R=0.287, p=101,745 Pa

But I just don't know how to use the correction factors. Should I take an average of both of them? Should I have two air densities?
Any help you make have would be much appreciated.
Thanks
 
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  • #2
I think there might be correction factors for humidity and altitude which might be in mm of Hg?
 

Related to Calculating air density from a barometer?

What is air density?

Air density refers to the mass of air per unit volume. It is a measure of how much air is present in a particular space or environment.

How is air density calculated?

Air density is calculated by dividing the mass of air by its volume. This can be done using the ideal gas law, which takes into account factors such as temperature, pressure, and the number of moles of gas present.

Why is a barometer used to calculate air density?

A barometer is used to measure atmospheric pressure, which is an important factor in calculating air density. This is because air density is directly related to pressure - as pressure increases, so does air density, and vice versa.

What are the units of measurement for air density?

Air density is typically measured in kilograms per cubic meter (kg/m3) in the SI system of units. In some cases, it may also be expressed in grams per cubic centimeter (g/cm3) or pounds per cubic foot (lb/ft3).

How does air density affect weather and flight?

Air density plays a crucial role in determining weather conditions, as it affects the movement of air masses and the formation of clouds. It also impacts flight, as changes in air density can affect the lift and performance of aircraft.

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