metric system conversions. standard units of measure
TRANSCRIPT
Metric System Conversions
Standard Units of measure
How did we get them?The kilogram is equal to the mass of the international
prototype of the kilogram: a piece of platinum-iridium alloy kept at the International Bureau of Weights and Measures in France
The meter is the length of the path travelled by light in vacuum during a time interval of 1/299 792 458 of a second.
The ampere is that constant current which, if maintained in two straight parallel conductors of infinite length, of negligible circular cross-section, and placed 1 meter apart in vacuum, would produce between these conductors a force equal to 2 x 10 -7 newton per meter of length.
Why is it easy again?Base units of tenMoving up and down the scale
Prefixes attached to SI units.
Why the prefixes?The mass of the earth is
5,984,000,000,000,000,000,000,000,000grams
I would much rather just say, the mass of the earth is 5984 yottagrams.
KILO1000Units
HECTO100
Units
DEKA10
UnitsDECI
0.1Unit
CENTI0.01Unit
MILLI0.001Unit
MetersLitersGrams
Ladder Method
How do you use the “ladder” method?
1st – Determine your starting point.
2nd – Count the “jumps” to your ending point.
3rd – Move the decimal the same number of jumps in the same direction.
4 km = _________ m
12
3
How many jumps does it take?
Starting Point Ending Point
4.1
__.2
__.3
__. = 4000 m
Mental Break-Conversion JokesRatio of an igloo's circumference to its
diameter = Eskimo Pi
1 millionth of a mouthwash = 1 microscope
Time it takes to sail 220 yards at 1 nautical mile per hour = Knotfurlong
Time between slipping on a peel and smacking the pavement = 1 bananosecond
2,000 mockingbirds = 2 kilomockingbirds
SMECMU!!!! (Not quite easy enough for a caveman to do)
Steps 1-2Step 1- Estimate your answer’s size. Use the
SMECMU analogy!
Step 2- Write down the number you wish to convert to another unit, with the old unit still on it.
Step 3-4Step 3-Write down the conversion factor, with the old unit
on the bottom, and the new unit on the top.
Step 4- Cancel out the old number with the bottom number as much as you can. The old unit should cancel out completely. Multiply by the new unit’s number, and get your answer in the new unit!
Example - Step 1Convert 100 cm to metersIs it going to get bigger or smaller?
Smaller!
Step 2Step 2- Write down the number you wish to convert to
another unit, with the old unit still on it.
100cm
Step 3Step 3-Write down the conversion factor, with the
old unit on the bottom, and the new unit on the top.How many centimeters are in a meter?
100cm 1m100cm
Step 4Step 4- Cancel out the old number with the bottom number as
much as you can. The old unit should cancel out completely. Multiply by the new unit’s number, and get your answer in the new unit!
Quick FactsTop beach volleyball players can jump
about 75 centimeters off the sand -- about the height of a Great Dane at its shoulders.
Female gymnasts execute precise movements on a balance beam that is only 10 centimeters wide -- about the width of a paperback novel.
No Naked Numbers!