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Measurement

# Under pressure

In this video we replicate Pascal's famous experiment that showed atmospheric pressure was due to the column of the weight of the air above. To test this we build a simple pressure measuring device, make measurements around Boston, and then use the ideal gas law to calculate the pressures we measured. License: Creative Commons BY-NC-SA More information at http://k12videos.mit.edu/terms-conditions. Created by MIT+K12.

## Want to join the conversation?

• Doesn't the weather each day also change the pressure?
• Whats the best unit to measure cups?
• That is a very outstanding question. The cup is a customary unit of measurement for volume.
• I never knew that there was pressure in the air!
• yup, it's like a motorcycle on your head for your whole life, which is a fact. :D
• What is the most common unit for measuring?
• The most common direct unit for measuring atmospheric pressure is kPa, which is used in the video.
(1 vote)
• What is the Bunker Hill Monument?
(1 vote)
• Why did the linear regression equation say R^2, not R?
• The atmosphere has pressure on everything even on us. We do not feel it due to the same pressure in our body. In the case of a non living thing like a book how it does not get smashed when the atmosphere does have pressure equally on the book?
• Does the pressure change because of the temperature?
(1 vote)
• In an open system (like our Earth), no, the pressure does not correlate with the temprature but it does affect the weather, rainfall, and cloudiness. In a closed system like a water bottle, the hotter it gets, the higher the pressure. Almost everything in the universe expands when it gets hotter.