0We have used a thermometer to measure the temperature of the lab we are working in. The instrument has an incertainty of 0.5 °C. Which of the following measurements cannot be admissible? (They can be more than... 0!)
A. 22.2 °C
B. 22.0 °C
C. 22 °C
D. 21.5 °C
E. 22.3 °C
F. 22.5 °C
Ans. A, C, E
CONTEXT Age 14. We are at the beginning of the new year. Students have already studied what a measurement means, how an instrument must be used and what are its features. They are expected to be aware that their particular thermometer don't allow to read values like 22.2 °C and 22.3 °C, because in that instrument we can read just 21.5 °C, 22.0 °C, 22.5 °C and so on. Furthermore, they have to understand that also 22 °C is wrong, because such a value would imply an uncertainty of 1 °C or 2°C: it's a bit tricky for them, however they need to cope with these types of «trifles»...