Dressen-SI Units/Metric

UNIT 2Measurements and Calculations : 

UNIT 2Measurements and Calculations After today you should understand: -Difference between qualitative and quantitative observations -What SI units are -Difference between accuracy and precision -How to do metric conversions

Types of ObservationsQualitative versus Quantitative : 

Types of ObservationsQualitative versus Quantitative Qualitative (quality) – Observations that deal with descriptions and comparisons of objects. These observations are subjective in nature. (Your senses, ie. smell, sight, touch) Which type of observation is used more regularly in science? Why? Quantitative (quantity) – Observations that contain a numerical component and usually are made with some type of instrument. (Use of a tool)

Quote of the Day : 

Quote of the Day Scientists are explorers. Philosophers are tourists. Richard Feynman

SI Base Units : 

SI Base Units SI is an abbreviation Le Systeme International d’Unites

Derived SI Units : 

Derived SI Units

Volume and All That Cubed Stuff : 

Volume and All That Cubed Stuff

Accuracy versus PrecisionThey are not the same thing!!! : 

Accuracy versus PrecisionThey are not the same thing!!!

METRIC CONVERSION : 

METRIC CONVERSION How to convert within the metric system © Copyright 2003 - 2004.  M. J. Krech. All rights reserved.

The pneumonic: : 

The pneumonic: King Henry Died Unexpectedly Drinking Chocolate Milk Memorize      this!

You must also know… : 

You must also know… …how to convert within the Metric System. Here’s a good device: On your paper draw a line and add 7 tick marks:

Next: : 

Next: Above the tick marks write the abbreviations for the King Henry pneumonic: k h d u d c m Write the units in the middle under the “U”. m L g 1000 100 10 1 0.1 0.01 0.001 1 x 103 1 x 102 1x101 1 x 10-1 1 x 10-2 1 x 10-3

Let’s add the meter line: : 

Let’s add the meter line: k h d u d c m kilo hecto deca deci centi milli km hm Dm m dm cm mm L g 1000 100 10 1 0.1 0.01 0.001 1 x 103 1 x 102 1x101 1 x 10-1 1 x 10-2 1 x 10-3

Let’s add the liter line: : 

Let’s add the liter line: km hm Dm m dm cm mm kL hL DL L dL cL mL k h d u d c m kilo hecto deca deci centi milli

Let’s add the gram line: : 

Let’s add the gram line: km hm Dm m dm cm mm kL hL DL L dL cL mL kg hg Dg g dg cg mg k h d u d c m kilo hecto deca deci centi milli

How to use this device: : 

How to use this device: Look at the problem. Look at the unit that has a number. On the device put your pencil on that unit. Move to new unit, counting jumps and noticing the direction of the jump. 3. Move decimal in original number the same # of spaces and in the same direction.

Example #1: : 

Example #1: Look at the problem. 56 cm = _____ mm Look at the unit that has a number. 56 cm On the device put your pencil on that unit. k h d u d c m km hm Dm m dm cm mm

Example #1: : 

Example #1: k h d u d c m km hm Dm m dm cm mm Move to new unit, counting jumps and noticing the direction of the jump! One jump to the right!

Example #1: : 

Example #1: Move decimal in original number the same # of spaces and in the same direction. 56 cm = _____ mm 56.0. Move decimal one jump to the right. Add a zero as a placeholder. One jump to the right!

One last caution: : 

One last caution: Be careful NOT to count the spot you start from, where you put your pencil point. Only count the jumps!

Practice these problems : 

Practice these problems 1m = ______ km 1m = ______ dm 1m = ______ cm 1m = ______ mm 250L = _________ cL 1 kg = __________ g 1260 mm ________ cm .08 dm __________ mm