Lesson 1

In the last two Self-Checks you noticed that different measuring devices have different precision. Often what is being measured determines which device will be used and the degree of precision required.

So far, you have learned that there are two important considerations when measuring an object—accuracy and precision. You will learn about another important consideration, calibration, in the next Try This.

Try This 2

1. To ensure the accuracy of fuel volume, gas pumps are calibrated. You may have noticed during a recent visit to a gas station that the fuel pumps are calibrated at 15°C? What does this mean?
2. What might occur if a fuel pump goes through a long period of time without proper calibration?
3. How would changes in temperature affect the accuracy of one litre of gas?
4. The precision of a gas pump is 0.001 L. Explain why this number is so small.

Save your responses in your course folder.

Share 2

With a partner or in a group, share your answers from Try This 2 and answer the following questions.

1. Some road signs indicate distances using a precision of 1 km. In larger cities some road signs use a precision of 0.1 km. Explain why this is the case.
2. When might road signs be inaccurate? How often should they be updated?
3. Can you think of other examples of precision and accuracy in everyday life?

If required, place a summary of your discussion in your course folder.