Mercury Barometer: Does Temperature Affect Height?

In summary, the height of a mercury barometer is affected by temperature due to thermal expansion of the mercury. This relationship is not linear and the height increases at a faster rate as temperature increases. The standard temperature range for this effect is between 0°C and 100°C. However, the height of a mercury barometer alone cannot accurately measure temperature due to other factors such as atmospheric pressure and altitude. Other instruments, like thermometers, are more suitable for this purpose. Aside from temperature, changes in atmospheric pressure, altitude, and surface tension of the mercury can also affect the height readings of a mercury barometer.
  • #1
touqra
287
0
Does the temperature of the mercury affects the height of the mercury column in a barometer?
 
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  • #2
Yes, it does. Mercury is subject to thermal expansion and its vapor pressure varies with temperature.
 
  • #3
touqra said:
Does the temperature of the mercury affects the height of the mercury column in a barometer?
The vapor pressure is less 0.01 mm Hg below 320 C; this would not be measurable.

The thermal expansion coefficient of mercury is 0.0002 per degree. You can calculate yourself the temperature change needed to get en error of one mm Hg.
 

1. How does temperature affect the height of a mercury barometer?

The height of a mercury barometer is affected by temperature due to the thermal expansion of the mercury. As the temperature increases, the mercury expands and takes up more space, causing the height of the barometer to increase. On the other hand, a decrease in temperature causes the mercury to contract and the height of the barometer to decrease.

2. Is there a specific temperature range that affects the height of a mercury barometer?

Yes, there is a specific temperature range that affects the height of a mercury barometer. This range is between 0°C and 100°C, or the freezing and boiling points of water. This is because these are the standard reference points for temperature measurement and the scale used for the mercury barometer is based on these points.

3. How does the height of a mercury barometer change with temperature?

The change in height of a mercury barometer with temperature is not linear. As the temperature increases, the height of the barometer increases at a faster rate. This is because the thermal expansion of mercury is not constant and varies with temperature.

4. Can the height of a mercury barometer be used to accurately measure temperature?

No, the height of a mercury barometer alone cannot be used to accurately measure temperature. This is because the relationship between temperature and height is not linear and can vary depending on factors such as atmospheric pressure and altitude. Other instruments, such as thermometers, are more suitable for measuring temperature.

5. What other factors can affect the height of a mercury barometer?

Aside from temperature, the height of a mercury barometer can also be affected by changes in atmospheric pressure and altitude. This is because the weight of the air above the barometer can influence the height of the mercury column. Additionally, changes in the surface tension of the mercury due to impurities or vibrations can also affect the height readings.

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