Barometer Planet: How a Barometer Works

In summary, the rise of mercury in a barometer tube is due to the atmospheric pressure outside pushing down on the mercury inside. This creates a vacuum that allows the mercury to rise up the tube. This is also why you can drink through a straw.
  • #1
Misr
385
0
[PLAIN]http://www.barometerplanet.com/wp-content/uploads/2009/09/merc_barometer.jpg [Broken]

What makes mercury rise in the tube?Does atmospheric pressure carries the mercury in the tube?Is that true?
 
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  • #2
Misr said:
[PLAIN]http://www.barometerplanet.com/wp-content/uploads/2009/09/merc_barometer.jpg [Broken]

What makes mercury rise in the tube?Does atmospheric pressure carries the mercury in the tube?Is that true?

Think about what would happen if the whole thermometer were in vacuum. The mercury would have no reason to climb the tube; it would just pool at the bottom. Vacuum inside, vacuum outside.

Now, push down a little bit on the mercury outside the tube. It's going to rise up the tube a little.
 
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  • #3
Yeah,so air pushes on the mercury in this basin,(or whatever it is called)and the mercury in turn pushes up on the mercury of the tube
 
  • #4
Misr said:
Yeah,so air pushes on the mercury in this basin,(or whatever it is called)and the mercury in turn pushes up on the mercury of the tube

Right. That's also why you can drink through a straw.
 
  • #5
Ok thanks
 

1. What is a barometer and how does it work?

A barometer is a scientific instrument used to measure atmospheric pressure. It works by using a sealed chamber of air that expands or contracts based on changes in atmospheric pressure. This expansion or contraction is then measured and displayed on a scale.

2. What is the history behind the invention of the barometer?

The barometer was invented in the 17th century by Italian physicist Evangelista Torricelli. He was inspired by the idea that air had weight and that changes in air pressure could be used to predict weather patterns. Torricelli's invention revolutionized the field of meteorology.

3. What are the different types of barometers?

There are two main types of barometers: mercury barometers and aneroid barometers. Mercury barometers use a column of mercury to measure atmospheric pressure, while aneroid barometers use a flexible metal chamber that expands or contracts based on changes in pressure.

4. How accurate are barometers in predicting weather?

Barometers are very accurate in predicting short-term weather changes, such as sudden drops in atmospheric pressure indicating an incoming storm. However, they are less accurate in predicting long-term weather patterns.

5. Can barometers be used for anything other than measuring atmospheric pressure?

Barometers can also be used to measure altitude. This is because as altitude increases, atmospheric pressure decreases. By measuring the changes in pressure, barometers can determine the altitude of a location.

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