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Measurement and Matter

Distinguishing accuracy and precision
Four research teams measured the speed at which signals travel down a certain type of nerve fiber, and what each team wrote in its team notebook is shown
the table below.
Suppose a later and more reliable measurement gives 13.0 m/s for the signal speed in the same type of nerve fiber. Decide which of the earlier measurements
was the most accurate, and which was the most precise.
team
A
B
C
D
what was written
in the notebook
"11.0m/s ± 2.0%"
"between 13.0m's and 14.0m/s"
"15.m/s"
14.0m/s + 0.1m/s"
most accurate
measurement
most precise
measurement
X

Measurement and Matter Distinguishing accuracy and precision Four research teams measured-example-1
User Louth
by
6.3k points

1 Answer

4 votes

The most accurate measurement among the earlier measurements is from Team D, with "14.0m/s + 0.1m/s."

How did we arrive at this assertion?

To determine which of the earlier measurements was the most accurate and which was the most precise, let's first understand the concepts of accuracy and precision.

1. Accuracy: Accuracy refers to how close a measured value is to the true or accepted value. In this case, the more accurate measurement is the one that is closest to the later and more reliable measurement of 13.0 m/s.

2. Precision: Precision refers to how close repeated measurements are to each other. A more precise measurement has less variation or spread among multiple measurements.

Let's evaluate each team's measurement:

- Team A: "11.0m/s ± 2.0%" - This indicates a range of values, and the midpoint of the range is 11.0 m/s. Given the later measurement of 13.0 m/s, Team A's measurement is not accurate, as it is quite far from the true value.

- Team B: "between 13.0m/s and 14.0m/s" - This measurement is accurate because it includes the later and more reliable measurement of 13.0 m/s. However, it is not precise, as it provides a range rather than a specific value.

- Team C: "15.m/s" - This measurement is not accurate, as it is significantly higher than the later measurement of 13.0 m/s.

- Team D: "14.0m/s + 0.1m/s" - This measurement is accurate, as it is close to the later measurement of 13.0 m/s. It is also precise because it provides a specific value with a small uncertainty (±0.1 m/s).

In conclusion, the most accurate measurement among the earlier measurements is from Team D, with "14.0m/s + 0.1m/s." The most precise measurement among the earlier measurements is also from Team D, as it provides a specific value with a small uncertainty.

So, the letter "D" represents both the most accurate and most precise measurement.

User Lee Price
by
7.4k points