Add to your King Henry Slide in your spiral notebook''

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Add to your King Henry Slide in your spiral
notebook..
King Henry Died Unexp. Drink.
Choc. Milk
Made Nastily
km m
cm mm
um nm
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What unit would you use to measure the distance
from the Cafeteria to the Office?
Yes, the METER !
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What unit would you use to measure the distance
from Amherst to Holyoke?
All right ! The KILOMETER would be the best!
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What unit would you use to measure the size of a
virus, or a molecule?
Tough one. But thats the NANOMETER !
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What unit would be best for measuring the length
of your science binder, which I know you have
with you?
Yup, your pal the CENTIMETER!
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Compared to English units, about how long is a
meter?
Meter stick, yard stick, pretty close. Actually
a meter is about 39 inches, so its a little bit
longer than a yard.
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Compared to English units, about how long is a
centimeter?
Its about the size of the tip of your little
finger around ½ inch
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And about how long is a kilometer, compared to a
mile ?????????
A kilometer is 0.6 miles long, so it is roughly ½
mile
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OK, lets talk prefixes.. What does the prefix
centi- mean ?
Right! 1 hundredth, also known as 1/100, or .01
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And what does the prefix kilo- mean?
Bingo! It does mean one thousand, aka 1,000
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OK, so what about milli- ?
One thousandth, or 1/1000, or .001 Theres a
very big difference between a millimeter and a
kilometer, right?
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So now that you mention it, what IS the
difference between a millimeter and a kilometer?
How many millimeters make up one kilometer?
There are 1,000 millimeters in a meter, and 1,000
meters in a kilometer, so its 1,000 x 1,000
1,000,000 mm in a km !
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How can you describe the size of a nanometer ?
A nanometer is pretty darn small. There are
1,000 nm in a micrometer (um) 1,000,000 nm in a
millimeter (mm) One billion nm in a meter!
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Lets do some math. YAY !!!!
3.529 x 100
352.9
9.8 x 100,000
980,000
0.002
.0002 x 10
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Multiplyings good.how about dividing by 10s?
77.413
77413 1,000
Dividing moves the decimal point to the left
0.20298 10,000
.000020298
Remember to count how many places the decimal
point moves, not the number of zeros
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So you measure your lettuce plants, and come out
with these numbers 5 cm, 5.2 cm, 4.9 cm, 4.9 cm
and 5.1cm What is the average height of those
plants?
If you said 5.0 cm, youre right! Why is that?
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So how do you know how many significant figures
you have in a measurement?
You remembered! Your last significant digit is
the first estimated digit, so your lettuce
measurements can only go to tenths of a
centimeter. You must round 5.02 to 5.0 cm
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So when you use your calculator to multiply or
divide, youve got to limit the number of
decimals in your answer to the number you had in
your measurements.
If you are using a tool that is calibrated to
very small units, you will be able to get close
to the true measurement. This is called
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YES !!!! ACCURACY !
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And if you are playing horseshoes, and every
single time you throw the horseshoe it lands on
the porch, you may not be accurate, but you
certainly are
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Uh huh, Youre PRECISE all right. Maybe not a
very good horseshoe player, but very consistent.
So. Last question
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How do you measure accurately?
You measure to the nearest calibrated unit, then
estimate the next digit.
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OKAY, youre good to go! Study your vocabulary
tonight, and read through your notes. And
remember to bring your materials with you to
class!