In which of the following devices is the thermal expansion considered a disadvantage?
A
Fire alarm
B
Thermostat
C
Bimetallic thermometer
D
Balance wheel of a watch
Verified Correct Answer: D.
Physical Principles & Numerical Solution
Thermal expansion can affect accuracy and timekeeping in a watch's balance wheel, making it disadvantageous in this application.
Source: WAEC / JAMB / NECO Classroom Archive (Record #72065)