Question

Liquid thermometers work on the principle of ________.

• A. Thermal expansion
• B. Heat conduction
• C. Heat capacity
• D. Specific gravity

Answer 1

The correct option is A Thermal expansion

Liquid-in-glass thermometers are based on the principle of thermal expansion of substances. A liquid in a glass tube (called a capillary) expands when heated and contracts when cooled.[2]
A calibrated scale can then be used to read off the respective temperature that led to the corresponding thermal expansion.[1]