TOPIC 11 – MEASUREMENT AND DATA PROCESSING
11.1 UNCERTAINTIES AND ERRORS IN MEASUREMENT AND RESULTS – Part 1
A. Qualitative vs. Quantitative measurements/observations
1. What is the difference between qualitative and quantitative observations? (Your answers should reveal
an understanding of the definitions for qualitative and quantitative.)
2. Write an example of a quantitative observation that you may make at home or at school.
3. Why are instruments such as rulers, scales (balances), thermometers, etc. necessary?
B. Units
4. How many milligrams are there in one kilogram?
5. How many meters are in 21.5 km?
6. What is the difference between a Mm and a mm? Which is larger one Mm or one mm?
C. Accuracy and Precision
Boiling temperature/C
Test Group A Group B Group C Group D
190.0 95.0 99.0 102.5
291.0 100.0 100.0 100.0
390.5 101.0 99.5 101.0
Range (highest
result – lowest
result)
Mean 90.5
1. Work out the mean temperature for each set of results.
2. Which group has measured an average boiling temperature closest to the expected value, if the pressure is 1 atm?
3. Which group has the most accurate mean result?
4. Which group has the most precise set of readings?
5. A set of data might be described as:
accurate and precise
inaccurate and precise
accurate and imprecise
inaccurate and imprecise.
Explain why.
6. One of the people in group A was not happy with the group’s result.
