What properties explain the behavior of liquid-filled thermometers?

Answer 1

a liquid filled thermometer reacts to the temperature it is subject to; by the liquid increasing in pressure and expanding , which results in movement of the liquid /"medium" that is used to fill it ; in most cases ;; Mercury substance .

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note , whilst the most common type of device used is the mercury in glass thermometer which is used in science laboratories .

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but be aware that there are other types used; but in industrial applications.

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1 type used in a engineering role ; is mercury in steel type of thermometer detector .

this is a measuring device which has a steel sensor device ; maybe about 2 inches 50 . mm . length , and this is joined to a steel capillary tube which has some degree of flexibility , and will have a long length until it is connected to the measuring scale .

the capillary tube has a hollow interior , which allows the mercury fluid to move within when subject to heat / and expand .

the increase in pressure is effected to another device called the measuring pressure tube .

the tube is commonly known as a bourdon tube pressure gauge .

and once again the capillary tube will be connected physically to the gauge tube .

the increase in mercury pressure , will cause the fluid substance to expand and move upwards in the capillary tube to the bourdon tube in the gauge .

this action causes the bourdon tube to move by deflection , in an arc because the tube is tensile, and causes itself to move outward and this small movement , is transmitted by a small brass gear mechanism linkage to a central pointer system , which when moved and effected appears to move across a scale which consequently indicates a value on a scale .

and the operator can read off a value from the measuring scale .

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so the properties of a liquid filled thermometer are ;

it should have a safe method of being sealed fully across its structure body between the measuring sensing device to the measuring scale .

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this is because the accuracy of measuring system depends on the sealing .

and because the interior will contain a substance which is harmful to health .,

and the repeatability of measuring accuracy depends on safe

e sealing of pressure whithin the system,

Answer 2

Liquid-filled thermometers work based on the principles of thermal expansion, heat transfer, and capillary action. The liquid inside expands or contracts with temperature changes, causing it to rise or fall in the tube. This movement is magnified by the narrow capillary tube, allowing for precise temperature measurement.