Pressure of column of mercury

Pa. After some calculations, it was determined that the pressure is equal to 1360 hPa. The formula used was Pressure = pgh, where p is the density of mercury, g is the acceleration due to gravity (9.81 m/s^2), and h is the height of the column (10 cm). The "g" in the density value represents grams per centimeter cubed, and hPa stands for hectopascals, which is equivalent to 100 pascals.
  • #1
teng125
416
0
What is the pressure of a 10 cm high column of mercury
(ρ = 13,6 g/cm^3) in hPa?

i know that the formula is Pressure=pgh so i subs in 13.6g/cm^3 (9.81m/s^2) (10cm).
may i know what is the g in 13.6g/cm^3 belongs to??

is it equals to 9.81m/s^2??
and also what is hPa??i know Pa is pascal but don't know h

anybody pls help
thanx
 
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  • #2
hPa is 10^2, so 100 times a Pa. And assume g is 9.81ms^-2. I'm not sure what you mean "what the 'g' in 13.6g/cm^3 belongs to" question, but g is not a variable in there, it's an indication that the density is in grams per centimeter cubed, so keep the units in centimeters and grams, and the answer should be ok.

Levi
 
Last edited:
  • #3


I can provide a response to this question. The g in 13.6g/cm^3 represents the acceleration due to gravity, which is approximately equal to 9.81m/s^2 on Earth's surface. This value is used in the formula for pressure because it takes into account the weight of the mercury column.

hPa stands for hectopascal, which is a unit of pressure commonly used in meteorology. It is equal to 100 pascals (Pa). So, to convert the pressure from pascals to hectopascals, you would divide the value by 100.

Using the formula for pressure (P = pgh), we can calculate the pressure of a 10 cm high column of mercury with a density of 13.6 g/cm^3. Substituting the values, we get:

P = (13.6 g/cm^3)(9.81m/s^2)(10cm)
= 1335.36 g/cm/s^2
= 1335.36 Pa

To convert this to hPa, we divide by 100 and get a pressure of 13.35 hPa.

I hope this helps clarify any confusion. Please let me know if you have any further questions.
 

What is the "pressure of column of mercury"?

The pressure of column of mercury refers to the pressure exerted by a column of liquid mercury due to its weight. It is often used as a unit of pressure measurement in scientific experiments and is equivalent to 1 millimeter of mercury (mmHg).

How is the pressure of column of mercury measured?

The pressure of column of mercury is typically measured using a barometer, which is a device that contains a column of liquid mercury that is balanced against the atmospheric pressure. The height of the column is then used to calculate the pressure exerted by the mercury.

What is the relationship between the pressure of column of mercury and atmospheric pressure?

The pressure of column of mercury is directly related to atmospheric pressure. As atmospheric pressure increases, the height of the mercury column in a barometer also increases, indicating a higher pressure. As atmospheric pressure decreases, the height of the column decreases, indicating a lower pressure.

What is the significance of using mercury in pressure measurements?

Mercury is a commonly used liquid in pressure measurements due to its high density and low vapor pressure. This makes it more accurate and reliable compared to other liquids. However, due to its toxicity, alternatives such as water or oil are often used in modern pressure measurement devices.

How is the pressure of column of mercury used in weather forecasting?

The pressure of column of mercury is an important factor in weather forecasting as it can indicate changes in atmospheric pressure. A sudden drop in atmospheric pressure, indicated by a decrease in the height of the mercury column, can signal an approaching storm or weather front. Monitoring changes in pressure over time can help forecasters predict future weather patterns.

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