Two thermometers of identical construction have bulbs of equal volume and capillaries…
PHYSICS · Subjective · CBSE · Physics · Thermal Properties of Matter · Thermal Properties of Matter
Problem
Two thermometers of identical construction have bulbs of equal volume and capillaries of equal internal cross-sectional area. One uses mercury (real volumetric expansion coefficient 1.82×10−4K−1) and the other uses ethyl alcohol (real volumetric expansion coefficient 1.12×10−3K−1). The coefficient of linear expansion of the glass is 9.0×10−6K−1.
(a) Derive an expression for the increase in length of the liquid column per kelvin rise in temperature for either liquid.
(b) Using the above data, calculate the ratio of the sensitivity (length rise per kelvin) of the alcohol thermometer to that of the mercury thermometer.
(c) State two practical limitations of using alcohol in thermometers despite its higher sensitivity.