Barometers are instruments that are used to measure Barometric Pressure (air). This device has been an integral part of the British domestic scene since the early part of the 18th Century. It’s able to measure the weight of the column of air that extends from the instrument to the top of the atmosphere. Barometers are useful tools that help in weather forecasting, as changes in pressure are used to predict imminent weather changes.
It’s a known fact that these devices measures present air pressure, which is the weight of air above it at any one time. It is said that the air around us can be considered of as an ocean in which we all live and it is a fact that, higher we reach in the air, the thinner the air becomes and the air pressure is relatively less there. Hence to tackle any such situation these measuring gadgets will normally require specific setting for the altitude where it is going to finally rest.
The primary feature of a this instrument is to measure atmospheric pressure and this instrument can be seen with the weather forecasters as they measure air pressure. It is proficient in evaluating accurate air pressure because rising or falling atmospheric pressure indicates an approaching change in weather. One is also able to measure altitude, with these instruments as atmospheric pressures are inferior at high altitudes then at low altitudes.
Altitude can be easily measured through a unique type of barometer which is called an altimeter. This altitude measuring instrument works as, the air has weight exerts a pressure. It works on the principle which is as follows: the weight of air at the ‘top’ of the atmosphere presses down on the lower layers of the air and this air pressure can be easily measured through this typical. The average sea level air pressure is 103 kPa.
There are basically two types of Barometric Pressure measuring instruments which is known as Mercury and Aneroid.
Mercury: This particular device use various physical properties of mercury contained in a tube to measure the barometric pressure, which is also known as air pressure or atmospheric pressure. When the pressure lowers, it is an indication of storms, rain, or wind. On an occasion of increased pressure one would witness dry, fair weather is on the way. All of these reading are only possible with the help of mercury barometers.
Aneroid: For accuracy aneroid barometers are used for measuring the absolute atmospheric pressure. These instruments are used basically for height determination. The process of height determination depends on measurements of atmospheric pressure differences which can be easily detected this particular device. This device does not contain liquid and is made of a corrugated steel box which is partially evacuated of air. The working principle of this device is related to its parts that includes a tap of the box presses against a strong spring. In an event of the air pressure rising the top of the box is pressed inwards and if the pressure decreases the top move upwards.
The movement of the top, due changes in pressure is magnified by a system of levers connected to a small rod fixed on the top of corrugated steel box. The movement of the level enables a pointer to move over a suitable calibrated scale. This is how the exact measurements are can be read through this particular type.
