Barometer: Explained

A barometer is a scientific instrument used to measure atmospheric pressure. Atmospheric pressure is the force per unit area exerted on a surface by the weight of the air above that surface in the Earth's atmosphere. A barometer is an important tool for meteorologists as it helps in predicting short-term changes in the weather, particularly for forecasting storms.

Types of Barometers

There are two main types of barometers:

1. Mercury Barometer: This type of barometer uses a column of mercury to measure atmospheric pressure. As the atmospheric pressure changes, it causes the level of mercury in the column to rise or fall.
2. Aneroid Barometer: An aneroid barometer uses a small, flexible metal box called an aneroid cell. As the atmospheric pressure changes, the cell expands or contracts, which is then converted to a pressure reading on a dial.

How Barometers Work

Barometers work based on the principle that as atmospheric pressure increases, the weight of the air above the barometer increases, causing the mercury level or the aneroid cell to respond accordingly. This change in the height of the mercury column or the movement of the aneroid cell is then used to determine the atmospheric pressure.

Study Guide: Barometer

1. What is the main purpose of a barometer?

The main purpose of a barometer is to measure atmospheric pressure.

2. How does a mercury barometer work?

A mercury barometer works by using a column of mercury to measure atmospheric pressure. As the pressure changes, it causes the level of mercury in the column to rise or fall.

3. What is the difference between a mercury barometer and an aneroid barometer?

A mercury barometer uses a column of mercury, while an aneroid barometer uses a flexible metal box called an aneroid cell to measure atmospheric pressure.

4. Why is a barometer important for meteorologists?

A barometer is important for meteorologists because it helps in predicting short-term changes in the weather, particularly for forecasting storms.