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Dimensional Analysis for Conversions. Write the KNOWN, identify the UNKNOWN. EX. How many quarts is 9.3 cups?. 9.3 cups. =. ? quarts. Write the KNOWN, identify the UNKNOWN. EX. How many quarts is 9.3 cups?. 9.3 cups. =. ? quarts. Draw the dimensional “jumps”. 9.3 cups. =.
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Write the KNOWN, identify the UNKNOWN. • EX. How many quarts is 9.3 cups? 9.3 cups = ? quarts
Write the KNOWN, identify the UNKNOWN. • EX. How many quarts is 9.3 cups? 9.3 cups = ? quarts
Draw the dimensional “jumps”. 9.3 cups = ? quarts 9.3 cups x * Use charts or tables to find relationships
Insert relationship so units cancel. quart 1 9.3 cups x 4 cups *units of known in denominator (bottom) first *** units of unknowns in numerator (top
Cancel units 1 quart 9.3 cups x 4 cups
Do Math 1 quart 9.3 cups x 4 cups • Follow order of operations! • Multiply values in numerator • If necessary multiply values in denominator • Divide.
Do the Math 1 quart 9.3 x 1 9.3 cups x = 4 cups 1 x 4 9.3 = 2.325 quarts = 4
Try this: • How many seconds are in 6 minutes? ____ seconds (6o seconds = 1 minute) • How many centimeters are in 27 inches? ____ centimeters (1 inch = 2.54 centimeters)
Metric Conversions Ladder Method T. Trimpe 2008 http://sciencespot.net/
Why do we need units of measurement? • If I tell you that I weight 200, it will make a difference whether it is pounds or kilograms. • Kilograms are 2.2 times heavier than a pound!
Systems of Measurement • The English system was based on the King’s measurement. • Inch was based on the width of his thumb • Feet were the length of one foot • Yards were the circumference of the king’s waist But what happens when the king dies and his son’s measurements are LARGER?
International System of Units (SI units) • Metrics are used by SCIENTISTS • Based on standardized measurements • Used worldwide. • Based on multiples.
Ladder Method 1 2 3 KILO1000Units HECTO100Units DEKA10Units DECI0.1Unit CENTI0.01Unit MILLI0.001Unit MetersLitersGrams
Conversion Practice Compare using <, >, or =. 56 cm 6 m 7 g 698 mg Try these conversions using the ladder method. 1000 mg = _______ g 1 L = _______ mL 160 cm = _______ mm 14 km = _______ m 109 g = _______ kg 250 m = _______ km
Metric Conversion Challenge Write the correct abbreviation for each metric unit. Kilogram _____ Milliliter _____ Kilometer _____ Meter _____ Centimeter _____ Gram _____ Liter _____ Milligram _____ Try these conversions.. 2000 mg = _______ g 5 L = _______ mL 16 cm = _______ mm 104 km = _______ m 198 g = _______ kg 2500 m = _______ km