Class 7 Science Chapter 6

What is the use of clinical thermometer Class 7?

Clinical thermometers: The thermometers which are used to measure the temperature of the human body . A clinical thermometer consists of a long glass tube having a glass bulb at its one end and the other end is sealed. The glass bulb has mercury inside it. Glass tube has a Celsius scale marked on it.

: a thermometer for measuring body temperature that has a constriction in the tube above the bulb preventing movement of the column of liquid downward once it has reached its maximum temperature so that it continues to indicate the maximum temperature until the liquid is shaken back down into the bulb.

Clinical thermometers are meant for clinical purposes. It is developed for measuring the human body temperature . It is a long narrow glass tube with a bulb containing mercury at the end.

There are liquid-in-glass thermometers that contain a non-mercury silver substance Galinstan® . Galinstan liquid consists of tin, indium, and gallium. According to its manufacturer, Galinstan is not toxic when swallowed because it passes through the digestive system without effect.

What are old thermometers filled with?

In a mercury thermometer , a glass tube is filled with mercury and a standard temperature scale is marked on the tube. With changes in temperature, the mercury expands and contracts, and the temperature can be read from the scale. Mercury thermometers can be used to determine body, liquid, and vapor temperature.

What Was Thermometers Filled With Before Mercury? Brandy was used to measure temperature long before mercury filled thermometers were available.

Mercury is contained in many products, including:

These thermometers are used in clinics by doctors , it is a clinical thermometers they are also called a doctor's thermometers or medical thermometers. Most show both Celsius scale and Fahrenheit temperature scales, and run from 35 degree Celsius to 42 degree Celsius.

How does a Class 7 clinical thermometer measure temperature?

Place the bulb of the thermometer under the tongue. Wait for one minute, take the thermometer out and note the reading keeping the level of mercury along the line of sight . This reading gives the exact body temperature. It is necessary to state the temperature with its unit denoted by °C.

There are non-mercury thermometers with temperature and accuracy ranges equal to most mercury thermometers. An exception is on the high end of the temperature scale. Until recently 260° C was the typical limit for non-mercury thermometers.

Most uses have been discontinued . Some medicines use small amounts of these compounds as preservatives. Learn about the use of thimerosal, a mercury-containing preservative, in vaccines. In addition, mercury is still used in skin lighteners and anti-aging products for the skin.

Gas-fired appliances, including ovens, water heaters, furnaces, poll heaters, and appliances in some recreational vehicles , may contain mercury. Older models may have pilot light sensors containing mercury.

How can I get mercury at home?

You might be surprised to learn where mercury is found in your home and school. Thermometers (fever, cooking, outdoor), thermostats, fluorescent lamps, button batteries, and some switches or relays can all be a source of mercury.

A clinical thermometer works on the principle of expansion of matter due to heat . The liquid in the bulb heats up and expands, proportional to the temperature. It rises up the capillary tube. A properly calibrated thermometer can thus help tell what the temperature is.

A medical thermometer (also called clinical thermometer) is used for measuring human or animal body temperature.

A clinical thermometer is a thermometer used to measure human body temperature . Most made in the 20th century are mercury-in-glass thermometers. They are accurate and sensitive, having a narrow place where the mercury level rises very fast. A kink in the tube stops the mercury level from falling on its own.

What is clinical thermometer Ncert?

Clinical thermometer is used to measure our body temperature . The range of this thermometer is from 35°C to 42°C. For other purposes, we use the laboratory thermometers. The range of these thermometers is usually from –10°C to 110°C.

: a thermometer for measuring body temperature that has a constriction in the tube above the bulb preventing movement of the column of liquid downward once it has reached its maximum temperature so that it continues to indicate the maximum temperature until the liquid is shaken back down into the bulb.

It is basically used to measure the temperature of human body . This thermometer is used to measure the temperature of all things, except the human body. A clinical thermometer has a temperature range of only 35 ºC to 42 °C.

As long as you don't expose your skin to the metal too much and you wash your hands after then you would be fine . If any mercury did absorb through your skin then the amount will be so small then you would urinate it out, leaving no mercury in your body and meaning it won't build up to harmful amounts.

How do you know if a thermometer has mercury in it?

How can I tell if my thermometer has mercury? Mercury is a silver-white to gray substance . If your thermometer is filled with a red liquid, your thermometer contains red dyed alcohol or mineral spirits and not mercury. These are safer alternatives to mercury fever thermometers.

Phase-out. As of 2012 , many mercury-in-glass thermometers are used in meteorology; however, they are becoming increasingly rare for other uses, as many countries banned them for medical use due to the toxicity of mercury.

There are several types of non-mercury-containing thermometers, including both liquid-in-glass and electronic digital thermometers . An example of an electronic digital thermometer is the platinum resistance thermometer. Others include the thermistor and the thermocouple.

Researchers at the NIST have identified two good candidates: carbon dioxide (CO 2) and sulfur hexafluoride (SF 6) . Both are chemically inert and have triple-points just below that of mercury.