Question

What is the principle of working of a thermometer?

• A. Thermal expansion of solids
• B. Thermal expansion of gases
• C. Thermal expansion of liquids
• D. All of the above.

Answer 1

The correct option is C Thermal expansion of liquids

Thermometers work on the principle of thermal expansion of liquids. Heat sensitive liquids are used as working liquids in thermometers. One of the most commonly used ones are mercury and alcohol.