Liquid in glass thermometer
In this instrument consist of a thick walled glass tube with a bore filled with a expanding fluid such as mecrury.
The principle used to measure temperature is that of the thermal expansion of the liquid.
Area of stem is less than the bulb
when we deep the bulb of thermometer in a hot liquid the mercury or expanding fluid in the bulb expans and rises upward.linear scale is mounted on the stem.so directly we can measure the temperature.
Advantages:
1)Good accuracy.
2)portable.
Disadvantages:
1)limited range
2)More time consuming
