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qbkr21

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- Sep 1st 2008, 01:31 PMqbkr21Quick Conversion question
Thanks

qbkr21

http://i137.photobucket.com/albums/q226/qbkr21/109.gif - Sep 1st 2008, 01:39 PMJhevon
$\displaystyle 1 \text{ Angstom} = 1.0 \times 10^{-10} \text{ meters}$ and $\displaystyle 1 \text{ meter} = 1.0 \times 10^9 \text{ nanometers}$

thus

$\displaystyle 1.4 {\color{red}\text{ Angstoms}} = 1.4 (\underbrace{{\color{red}1.0 \times 10^{-10} \text{ meters}}}_{\text{this replaces Angstoms}}) = 1.4 \times 1.0 \times 10^{-10} \times (\underbrace{{\color{red}1.0 \times 10^9 \text{ nanometers}}}_{\text{this replaces meters}})$

we just keep replacing the units with their equivalents

or, to do it your way:

$\displaystyle 1.4 \text{ Angstom} \times \frac {10^{-10} \text{ meters}}{1 \text{ Angstom}} \times \frac {10^9 \text{nanometers}}{1 \text{ meter}}$ - Sep 1st 2008, 01:46 PMqbkr21RE:
RE:

Where did I go wrong doing it my way? I'd like to figure out how the exponents in Scientific Notation correlate to the problem. If the sign changes if goes on top or bottom. Can you help me with this?

qbkr21 - Sep 1st 2008, 01:48 PMqbkr21RE:
What if we were given meters and told to turn them into Angstroms; would the 1.0 X 10^-10 become 1.0 X 10^10 since it would be put on the bottom?

- Sep 1st 2008, 01:53 PMqbkr21RE:
- Sep 1st 2008, 01:56 PMJhevon
to take something from the top and put it in the bottom, or vice versa, we change all the exponents to their negatives. but that is not necessary here. in the denominator we only have 1's. so we just multiply all the numerators together.

to answer your first question: yes, the negative sign stays on top. it is not necessary to move it to the bottom, so don't worry about it. moving it to the bottom will mess you up - Sep 1st 2008, 01:57 PMJhevon
- Sep 1st 2008, 01:59 PMqbkr21RE:
RE:

So would

1 Meter = 1 X 10^2 centimeters? - Sep 1st 2008, 02:00 PMJhevon
- Sep 1st 2008, 02:06 PMqbkr21RE:
Jhevon for some reason I have all of my units mixed up. Maybe you can help. Here are the units that I was given, can you correct them so that I can avoid future error?

http://i137.photobucket.com/albums/q226/qbkr21/111.gif - Sep 1st 2008, 02:11 PMJhevon
this has meters on the right and (prefix)meters on the left. this table is correct. in what we did, the coefficient of meter was 1. that is not the case in this table. you have to solve for 1 meter to do our problem

example: the table says,

$\displaystyle 1 \text{ nanometer} = 1 \times 10^{-9} \text{ meters}$

this is correct, but we want 1 meter = something nanometers. multiply both sides by $\displaystyle 10^9$ to obtain

$\displaystyle 1 \times 10^9 \text{ nanometers} = 1 \times 10^{-9} \times 10^9 \text{ meters} = 1 \times \times 10^{-9 + 9} \text{ meters} = 1 \text{ meter}$ - Sep 1st 2008, 02:18 PMqbkr21RE:
When we convert do we usually try and get meters by itself?

- Sep 1st 2008, 02:23 PMqbkr21RE:
- Sep 1st 2008, 02:25 PMJhevon
- Sep 1st 2008, 02:26 PMJhevon