what is a thermometer

When did mercury stop being used in thermometers?

The National Institute of Standards and Technology (NIST), which is working with EPA on this effort, announced on February 2, 2011 that it will no longer calibrate mercury-in-glass thermometers for traceability purposes beginning on March 1, 2011 Exit Exit EPA website.

Why don't they use mercury in thermometers?

The small silvery ball in a mercury thermometer can be dangerous if the glass breaks and the mercury is not cleaned up properly. The mercury will evaporate and can contaminate the surrounding air and become toxic to humans and wildlife . Each thermometer contains about .

Which thermometers do not use mercury?

Spirit thermometers use a non-toxic alcohol instead of mercury to register the temperature. Like liquid mercury, the alcohol expands in volume as it gets warmer, causing the liquid to move up the thin tube inside the glass thermometer. Digital thermometers contain a device called a thermoresistor.

Which mercury is used for thermometers?

Mercury is a liquid from -39 ºC to 357 ºC . Mercury's wide temperature range makes it much more versatile–you can use the same thermometer to measure a person's body temperature, check how cold the weather is, and even measure the temperature of cooked food.

Where does mercury in a thermometer come from?

The mercury-in-glass or mercury thermometer was invented by physicist Daniel Gabriel Fahrenheit in Amsterdam (1714). It consists of a bulb containing mercury attached to a glass tube of narrow diameter ; the volume of mercury in the tube is much less than the volume in the bulb.

Was mercury once used in thermometers?

People tend to associate mercury with its silvery liquid form - perhaps found in old thermometers . It was also used in electrical switches or relays that were built into machines until the mid-20th century, and it can be found in florescent lamps and even newer energy saving lamps.

When did thermometers start using mercury?

The more modern thermometer was invented in 1709 by Daniel Fahrenheit. It was an enclosed glass tube that had a numerical scale, called the Fahrenheit scale. The early version of this thermometer contained alcohol and in 1714 Fahrenheit developed a mercury thermometer using the same scale.

When was mercury last used in thermometers?

The National Institute of Standards and Technology (NIST), which is working with EPA on this effort, announced on February 2, 2011 that it will no longer calibrate mercury-in-glass thermometers for traceability purposes beginning on March 1, 2011 Exit Exit EPA website.

Why is mercury used?

Although many liquids could be used in pressure measuring devices, mercury is used because its high density requires less space . It is also a good conductor of electricity, so it is a useful component of electrical switches. Mercury is also used in dental fillings, paints, soaps, batteries, and fluorescent lighting.

Why mercury is used in thermometer Byjus?

Mercury is used in thermometer because: Mercury is a liquid which can flow but does not stick to the glass . It has high coefficient of expansion so that even a small rise in temperature brings about sufficient expansion which can be detected in the capillary of the calibrated part of the thermometer.