Table of Contents

- 1 Why does the height of the mercury column change from day to day?
- 2 What are the factors affecting barometric height?
- 3 Why is the height of mercury in a barometer independent of the cross sectional area of the tube?
- 4 Is the height of mercury column is equivalent to 1 atmosphere?
- 5 How tall is a column of mercury in the atmosphere?
- 6 How does a Torricelli barometer measure atmospheric pressure?

## Why does the height of the mercury column change from day to day?

Torricelli predicted that the height of the mercury column would change from day to day as the pressure of the atmosphere changed. Repeated experiments showed that the average pressure of the atmosphere at sea level is equal to the pressure of a column of mercury 760 mm tall.

## What are the factors affecting barometric height?

3 factors affecting the barometric (air) pressure are Temperature of air, Altitude or Elevation and Moisture. Temperature of air is inverse relationship to air pressure. When temperature falls and barometer it is shown the barometric pressure rise.

**What is the height of mercury column in a barometer?**

Measuring Atmospheric Pressure A pressure of 1 atm will support a column of mercury 76 cm high.

**How will the barometric height be affected if mercury was replaced by water in simple barometer?**

Answer: . The column of water inside the barometer would be 13,6 times higher, since the density of mercury is 13,6 times that of water.

### Why is the height of mercury in a barometer independent of the cross sectional area of the tube?

since A is cancelled out, the height of the mercury level is independent of the cross-sectional area. If the tubing were tilted at an angle of 15∘, the vertical height of the liquid would be the same so it would still work.

### Is the height of mercury column is equivalent to 1 atmosphere?

1 mmHg is equal to 133 Pa and 760 mmHg corresponds to 1 atm, which means the atmospheric pressure that supports a column of mercury 760 mm high.

**What is the height of mercury at 1 atm?**

76 cm high

LIQUIDS AND GASES A pressure of 1 atm will support a column of mercury 76 cm high. That is, a pressure of 1 atm will support a column of mercury 76.0 cm high. Deviations of the height of the column from the normal value of 76.0 cm reflect changes in the atmospheric pressure due to local weather conditions.

**How does the height of mercury affect the barometer?**

Some of the most important factors that affects the height of Mercury in the Barometer are: 1. Altitude: The density of air and the atmosphere above becomes less with height. Since pressure depends on weight, the atmospheric pressure also decreases with height. Therefore, the reading in the barometer tube falls as it is taken up in the atmosphere.

#### How tall is a column of mercury in the atmosphere?

Well, we know that 1 ⋅ atmosphere pressure will support a column of mercury that is 760 ⋅ mm high. And thus a mercury column, a mercury barometer, is an excellent means to monitor atmospheric pressure, or pressures LOWER than atmospheric pressure.

#### How does a Torricelli barometer measure atmospheric pressure?

When making a simple Torricelli barometer, the tube is initially fully filled with the substance (e.g. Mercury). It is then capped off and inverted into a basin containing the same fluid and the cap is taken off. This method actually causes a vacuum to be formed once the barometer’s fluid height changes when the atmospheric pressure is sensed.

**How does atmospheric pressure affect the length of a column?**

So column length is a good and visual gauge of the pressure. Of course, daily variations in atmospheric pressure will cause the length of the column to vary. Would the length of the column be the same at altitude?