http://www.ck12.org Chapter 1. Introduction to Physical Science
Precision
As you can see from the sketch above, the four golf balls did not land as close to one another as they could have. Each
one landed in a different part of the hole. Therefore, these shots are not very precise. Theprecisionof measurements
is how close they are to each other. If you make the same measurement twice, the answers are precise if they are the
same or at least very close to one another. The golf balls in the sketch below landed quite close together in a cluster,
so they would be considered precise. However, they are all far from the hole, so they are not accurate.
Q:If you were to hit four golf balls toward a hole and your shots were both accurate and precise, where would the
balls land?
A:All four golf balls would land in the hole (accurate) and also very close to one another (precise).
Summary
- Accuracy means making measurements that are close to the true value.
- Precision means making measurements that are close in value to each other but not necessarily close to the
true value.
Vocabulary
- accuracy: Closeness of a measurement to the true value.
- precision: Exactness of a measurement.
Explore More
Review the concepts of accuracy and precision at this URL. Then play the dart game until you obtain scores that are
both accurate and precise.