Measurement and Scientific Tools NOS Lesson 2 Description

Measurement and Scientific Tools NOS- Lesson 2

�Description: you are observing and saying what you observe. �Explanation: you are inferring and telling us why or how you know. Vocab Check

� Hash tag example �Precision-a description of how similar or close measurements are to each other. �Accuracy- a description of how close a measurement is to an accepted or true value. Why do we need SI? ? ?

�Bull’s eye Example �Why is it important for your watch to have accurate time? �How can a clock be precise, but not accurate? Bull’s Eye Example

�The Squirrel traveled 5 meters to get a an acorn. ◦ How far is that? �The Squirrel traveled 5 feet to get the acorn. ◦ How far is that? �Inches, ft, yards, miles �mm, cm, meters and Km �International system of Units (SI)internationally accepted system for measurement. Measurement

�Length= meters (m) �Mass=grams (g) �Time= seconds (s) �Volume= Liters (l) Base Units

�Meter stick �Group practice with a meter stick or rulers. Hands on

MILLIGRAMS 1000 mg = 1 g 1, 000 mg = 1 kg GRAMS 1 g = 1000 mg KILOGRAMS 1 kg = 1, 000 g 1 kg = 1, 000 mg 1, 000 g = 1 kg

�Kilo- (k) �Hecto- (h) �Deka- (da) �BASE UNIT �Deci- (d) �Centi-(c) �Milli- (m) Prefixes-what is a prefix?

USE THE STAIRS

�Come up with your own Mnemonic, prepare to share. �Kelly Mine. Has Dirty Underwear Don’t Check USE a MNEMONIC

Try these conversions, using the ladder method. � 1000 mg = _______ g � 1 L = _______ m. L � 160 cm = _______ mm � 1. 4 km = _______ m � 10. 9 cg = _______ kg �. 250 m = _______ km

�Description �Explanation �SI �Precision �Accuracy Vocab Check

�Significant Digits- Number of digits in a measurement that are used with a certain degree of reliabilitiy. ◦ All Exact digits + one that is estimated. SI still not good enough?

All nonzero numbers are significant 2. Zeros between nonzero numbers are significant 3. Final Zeros used after the decimal point are significant 4. Zeros used solely for spacing the decimal point are not significant. 1. Rules

Example 1. 234 1. 2 0. 023 0. 200 1, 002 3. 07 0. 001 0. 012 50, 600 Quiz Sig Figs Applied Rules

� Science Journal � Balances � Thermometer � Microscopes � Magnifying glass � Slide � Dissecting tools � Pipette � Flask � Graduated cylinder � Beaker � Test Tubes � Bunsen burner Scientific Tools