# What is a measurement

```Name: ____________________________________
Grade 8 Worksheet 3 Scientific Tools and Measurement
1. What is a measurement?
2. Why was the SI unit developed?
3. What are the SI units of length, mass, time, and temperature and the tools used to make those
measurements?
Quantity
SI Unit
Tools
length
mass
time
temperature
4. Which of the following measurements should be represented in scientific notation: the diameter
of a blood cell, the speed of a car, or the speed of light? Explain.
Refer to diagram on page 83 to answer the following question 5 and 6.
5. Which drawing shows high precision and low accuracy? Explain how you know.
6. Which drawing shows high accuracy and low precision? Explain.
7. How do scientists use computers?
8. Write the following numbers in scientific notation.
a. 0.0000000502 m
b. 61500000000 mg
9. What tool is used to magnify small objects?
10. The ‘accepted’ density of aluminium is 2.70 g/cm3. Two students used a balance and measuring
cylinder to measure the density of aluminium. The results obtained by each student are listed in
the table below.
Student A
Student B
2.2 g/cm3
2.71 g/cm3
2.3 g/cm3
2.69 g/cm3
2.5 g/cm3
2.68 g/cm3
2.4 g/cm3
5.81 g/cm3
Answer the following questions based on the table above.
Which student’s data is more accurate?
Which student’s data is more precise?
Which student’s data contains an outlier?
11. Look at each target and decide whether the “hits” are accurate, precise, both
precise, or neither accurate nor precise:
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