In this worksheet, we will practice defining measurement accuracy and precision and explaining different types of measurement errors that affect them.

**Q1: **

The diagram shows a target board and four sets of hits on it, (A), (B), (C), and (D). The shots were all aimed at the bull’s-eye of the target.

Which set of hits is both accurate and precise?

- A(C)
- B(B)
- C(D)
- D(A)

Which set of hits is neither accurate nor precise?

- A(C)
- B(B)
- C(A)
- D(D)

Which set of hits is accurate but not precise?

- A(C)
- B(A)
- C(B)
- D(D)

Which set of hits is precise but not accurate?

- A(B)
- B(D)
- C(A)
- D(C)

**Q2: **

Which of the following statements most correctly describes how zero measurement errors affect the accuracy and the precision of measurements?

- AZero errors decrease measurement precision.
- BZero errors decrease both the accuracy and the precision of measurements.
- CZero errors do not affect measurement accuracy or measurement precision.
- DZero errors decrease measurement accuracy.

**Q3: **

Which of the following statements most correctly describes how systematic measurement errors affect the accuracy and the precision of measurements?

- ASystematic errors decrease measurement precision.
- BSystematic errors decrease both the accuracy and the precision of measurements.
- CSystematic errors do not affect measurement accuracy or measurement precision.
- DSystematic errors decrease measurement accuracy.

**Q4: **

Which of the following statements most correctly describes how random measurement errors affect the accuracy and the precision of measurements?

- ARandom errors decrease measurement precision.
- BRandom errors decrease measurement accuracy.
- CRandom errors do not affect measurement accuracy or measurement precision.
- DRandom errors decrease both the accuracy and the precision of measurements.

**Q5: **

Which of the following statements most correctly describes the meaning of the precision of measurements?

- AA precise measurement is more accurate than an accurate measurement.
- BThe more precise the measurement of a quantity is, the closer the measured value is to the actual value of the measured quantity.
- CA precise measurement is made using a correct measurement method.
- DThe more precise the measurement of a quantity is, the smaller the predictable change that can be made between the measured value and other measured values of the same quantity.

**Q6: **

Which of the following statements most correctly describes the meaning of the accuracy of measurements?

- AAn accurate measurement has a value that is the same value when a quantity is repeatedly measured.
- BThe more accurate the measurement of a quantity is, the smaller the predictable change that can be made between the measured value and other measured values of the same quantity.
- CAn accurate measurement is made using a correct measurement method.
- DThe more accurate the measurement of a quantity is, the closer the measured value is to the actual value of the measured quantity.