Barometer Flashcard Sci7

Front

What is a barometer?

Back

A barometer is an instrument used to measure air pressure.

Front

What is the principle behind a mercury barometer?

Back

A mercury barometer measures air pressure by the height of mercury in a glass tube, which changes with variations in air pressure.

Front

What is the role of mercury in a mercury barometer?

Back

Mercury is used in a mercury barometer because it is dense and does not evaporate easily, allowing for accurate measurements of air pressure.

Front

How does air pressure affect the height of mercury in a barometer?

Back

When air pressure increases, it pushes down on the mercury, causing it to rise in the tube; when air pressure decreases, the mercury level falls.

Front

What is an aneroid barometer?

Back

An aneroid barometer is a type of barometer that uses a small, flexible metal capsule that expands or contracts with changes in air pressure.

Front

What is the relationship between altitude and air pressure?

Back

As altitude increases, air pressure decreases because there is less air above pushing down.

Front

What units are used to measure air pressure?

Back

Air pressure is commonly measured in units such as millibars (mb), inches of mercury (inHg), or pascals (Pa).

Front

What happens to air pressure during a storm?

Back

Air pressure typically decreases before a storm, which can indicate that stormy weather is approaching.

Front

How can barometers be used in weather forecasting?

Back

Barometers can help predict weather changes by monitoring air pressure trends; falling pressure often indicates worsening weather.

Front

What is the difference between absolute pressure and gauge pressure?

Back

Absolute pressure is the total pressure measured relative to a vacuum, while gauge pressure is the pressure measured relative to atmospheric pressure.