Lesson 4 — Taking accurate measurments

• Speed
• Middelbare school
• havo, vwo
• Leerjaar 2

TTO 2 – Science

Period 1 — Speed

This lesson

• Paragraph 4.2
  
• Working on workbook exercises
• Checking the calculations worksheet

Goals

• Explain the difference between accuracy and precision.
  
• Describe what is meant by significant figures
• Describe what is meant by reaction time.
• Describe how to measure time precisely.

Precision and accuracy

Precision:

How detailed your measurement is

Accuracy:

How correct your measurement is

Start §4.2 — Exercise

Step 1) Read §4.2, the part about precision and accuracy.

Step 2) When you and your neighbour have both read this section, Explain the difference between precision and accuracy to each other. Also explain what significant figures are.

Step 3) Write down what the difference is in your notebook.

Significant figures

Two measurements for a 400 meter sprint.

43 seconds

43,03 second

Significant figures

The amount of meaning numbers in a measurement.

Usain bolt

Time:

Yohan Blake

Time:

Justin Gatlin

Time:

2012 olympics — 100 m sprint

Usain bolt

Time: 10 s

Yohan Blake

Time: 10 s

Justin Gatlin

Time: 10 s

Their 2012 times

1 significant number

Usain bolt

Time: 9.6 s

Yohan Blake

Time: 9.8 s

Justin Gatlin

Time: 9.8 s

Their 2012 times

2 significant number

Usain bolt

Time: 9.63 s

Yohan Blake

Time: 9.75 s

Justin Gatlin

Time: 9.79 s

Their 2012 times

3 significant number

Precision and accuracy

Accuracy: How close the measurement is to the actual value of the thing being measured.

Precision: How refined the measurement is, shown in the number of significant numbers.

Significant figures: The amount of digits in a measurment that are meaningful for the measurement.

Reaction time

• The worksheet exercises
  

• Read the rest of 4.2
  

• Do the workbook exercises of 4.2
  

Goals

• Explain the difference between accuracy and precision.
  
• Describe what is meant by significant figures
• Describe what is meant by reaction time.
• Describe how to measure time precisely.