What does a mercury barometer look like?
A mercury barometer is a device that is used to measure the atmospheric pressure at a given location. The barometer consists of a vertical glass tube that is closed at one end. The closed-end is at the top and it sits in the mercury-filled basin placed at the bottom. It is an absolute pressure gauge.
How does a mercury barometers work?
The barometer works by balancing the weight of mercury in the glass tube against the atmospheric pressure, much like a set of scales. With an increased weight of air above the reservoir, the mercury level rises to a higher level.
Is a mercury barometer safe?
A mercury barometer in the home is no threat to your health.
What is barometer with diagram?
Simple barometer An inverted glass tube is standing in the bath of mercury and air pressure is exerted on the surface of mercury. The pressure at the top of the mercury column is zero as there is a vacuum there.
How accurate is a mercury barometer?
Barometers. The most commonly used type of barometer for calibration duties is the Fortin barometer. This is a highly accurate instrument that provides measurement inaccuracy levels of between ±0.03% of full-scale reading and ±0.001% of full-scale reading depending on the measurement range.
What are the disadvantages of mercury barometer?
Mercury barometer has the following disadvantages:
- It has a long glass tube with no protection to it.
- It requires zero adjustment before taking the reading.
- The barometer must be kept vertical to get the correct reading.
- The container in which the glass tube is inverted is open from the top.
How do you adjust a mercury barometer?
Barometer to be calibrated Align the heights of the ivory needle and the sensor inside the electric barometer. (2) Tap the vessel of mercury a couple of times gently and turn the adjustment screw slowly to raise mercury surface until it contacts the tip of an ivory pointer slightly.
How much does a good barometer cost?
The majority of barometers cost between $10 for basic digital models to $50 for large dial-type barometers. However, some ornate options can cost $200 or more.
What is the error of using mercury barometer?
The density of impure mercury is different from that of pure mercury. Hence, a barometer containing impure mercury will produce reading errors as the indicated pressure is proportional to the density of mercury. Barometric readings have to be reduced from the local acceleration of gravity to standard (normal) gravity.