1. NOS Lesson 2: Measurement and Scientific Tools

2. Warm-Up Activity
What’s the difference between an observation and an inference? Support your response with information from your notes.

3. Daily Objective
Why is it important for scientists to use the International System of Units?
What cause measurement uncertainty?
What are mean, median, mode and range?

4. Description and Explanation
Description – A spoken or written summary of observations
Qualitative Description – a description based on the use of your senses (sight, sound, smell, touch, taste)
Quantitative Description – a description based on the use of numbers and measurements.
Explanation – An interpretation of observations.

5. The International System of Units
International System of Units – the internationally accepted system for measurement.

6. Why would a scientist want to find the mean of a data set?
Warm-Up Activity
Why would a scientist want to find the mean of a data set?

7. Classwork Correct Lab Reports
Complete Understanding Science Content Review Sheet
Read Silently NOS12 – NOS18
Define NOS Lesson 2: Measurement and Scientific Tools Vocabulary Terms
Description
Explanation
International System of Units
Significant digits

8. What is a qualitative description? What is a quantitative description?
Warm-Up Activity
What is a qualitative description?
What is a quantitative description?
Give an example of both. NOS12

9. Review What’s the difference between a description and an explanation?
A description is a spoken or written summary of an observation. An explanation is an interpretation of an observation.
Why do scientists use the International System of Units?
The use of SI makes communication among scientists easier because scientists are using the same units.

10. SI Unit Prefixes
Prefixes (kilo-(1000), centi-(1/100), milli- (1/1000)) are used to indicate a fraction or a multiple of ten.
Scientists determine which prefix to use based on what they are measuring. For example, a human would be measure in kilograms, but an eraser would be measured in grams.

11. What are the SI units used to measure length, mass, and time?
Warm-Up Activity
What are the SI units used to measure length, mass, and time?

12. Guiding Questions NOS14-NOS15
What causes measurement uncertainty?
The last digit of any measurement is always an estimate.
What values do scientist often use to compare data they collected?
Scientists often use median, mean, mode and range.
What are mean, median, and mode?
Mean, median, and mode are values that are calculated to compare data. M
Mean of a data set is the sum of the numbers in the set divided by the number of entries in the set.
Median is the middle number in a data set when the data are arranged in numerical order.
Mode is the number or item that appears most often.

13. Significant Digits
Significant digits are the number of digits in a measurement that you know with a certain degree of reliability.
Examples:
1.02 has 3 Significant Digits
0.001 has 1 Significant Digit

14. Scientific Tools
Science Journal – Used to record observations, hypotheses, data, and conclusions of scientific investigations.
Rulers and Metersticks – measure length or distance
Glassware – measure volume or store liquids
Triple Beam Balance – measure mass
Thermometer – measure temperature
Streak Plate – Used to help scientists identify minerals.

15. Differentiate among mean, median, mode and range.
Warm-Up Activity
Differentiate among mean, median, mode and range.