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rams78110
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Hey quick basic question. Preface: I have been drinking a small bit (two regular beers over 2 hours) so I may be missing something here but I am pretty sure I'm not.

When something asks you to rank a series of numbers in scientific notation by magnitude, and not in least to greatest order, an exponent of -6 magnitude would be greater than an exponent of +3 magnitude right?

It was my understanding throughout my mathematical career that magnitude takes into account the number, regardless of positivity or negativity. I was told through our 'infallible' (very, very fallible. our professor corrects something weekly) online homework service that I got the following question wrong:

Rank these values according to magnitude: 2.110^5, 5.9 10^4, 4.510^-2, 9.010^-6, 8.110^-6

I ranked them (ignoring exponents to save time) 9.0, 8.1, 2.1, 5.9, 4.5

To my understanding, I did that correctly, and magnitude is magnitude and not 'from greatest to least'. Just want to make sure before I send off an email.
 
quidjibo
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Originally posted by rams78110
Hey quick basic question. Preface: I have been drinking a small bit (two regular beers over 2 hours) so I may be missing something here but I am pretty sure I'm not.

When something asks you to rank a series of numbers in scientific notation by magnitude and not in least to greatest order this does not make sense, an exponent of -6 magnitude would be greater than an exponent of +3 magnitude right? nope. -6 is of smaller magnitude than +3 when talking about numbers expressed as exponents. If they were not exponents but whole numbers or decimals then you'd be correct

It was my understanding throughout my mathematical career that magnitude takes into account the number, regardless of positivity or negativity. I was told through our 'infallible' (very, very fallible. our professor corrects something weekly) online homework service that I got the following question wrong:

Rank these values according to magnitude: 2.110^5, 5.9 10^4, 4.510^-2, 9.010^-6, 8.110^-6
in terms of "magnitude": the first value is the highest, the 5th is the lowest
I ranked them (ignoring exponents to save time) 9.0, 8.1, 2.1, 5.9, 4.5
it's all about the exponents first and foremost, the highest positive exponent is the highest order of magnitude
To my understanding, I did that correctly, and magnitude is magnitude and not 'from greatest to least'. Just want to make sure before I send off an email.


10^-2 = 1/10^+2
i suggest using your calculator to convert numbers expressed as negative exponents to decimals while you get the hang of this
Edited by quidjibo on Sep 4, 2013 13:33:39
Edited by quidjibo on Sep 4, 2013 13:05:20
Edited by quidjibo on Sep 4, 2013 12:53:02
 
Venkman
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Originally posted by quidjibo
10^-2 = 1/10^+2

5*10^-2 is of higher magnitude than 6*10^-2
but
5*10^+2 is of lower magnitude than 6*10^+2


no.
magnitude has to do with where you are at as far as a power of 10. you're thinking of the sheer value of the number, which is not what order of magnitude tells you.
5x10^-2 is of the same order of magnitude as 6x10^-2 because they are within the same power of 10


I left this in the other thread

Originally posted by seths99
the question asked: rank by magnitude. in my mind, that absolutely takes into account the sign of the exponent. 10^3 is five magnitudes of order GREATER than 10^-2. I think that by saying 'not in least to greatest order', they are saying that 9.0x10^6 is equivalent to 8.1x10^6, since they are both within the same order of magnitude.

but yes, when ranking by magnitude, the sign of the exponent matters. think of it this way, too, you're talking about factors of 10 in this situation, something that is equal to -3 factors of 10 (0.001)is definitely less than something that is 2 factors of 10 (100)
thinking about it just in terms of the absolute value of the order of magnitude serves no purpose that I can think of.


ed: I thought of a purpose right after hitting post: if you're working with metric conversions, then just knowing the absolute value of the order of magnitude would tell you how many places to move the decimal point. you would still need to know the sign to tell you which direction to move the point

 
quidjibo
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5*10^-2 is of higher magnitude than 6*10^-2
this is wrong so i deleted it
Edited by quidjibo on Sep 4, 2013 13:35:05
Edited by quidjibo on Sep 4, 2013 13:23:06
 
quidjibo
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just do all your exponent converting to decimal and you'll pick it up
 
PatrickStump
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Originally posted by HEY YOU GUYS
Anyone good at Calculus I could PM?


Still need help over a year later? I'm pretty solid at Calculus
 
Ahrens858
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calc is the woorst

im still pissed i have to take calc 2
 
Greenday4537
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Originally posted by Ahrens858
calc is the woorst

im still pissed i have to take calc 2


What's your major?
 
Venkman
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Originally posted by Ahrens858
calc is the woorst

im still pissed i have to take calc 2


calc 2 I could handle.
it was when I took calc 3 and they threw in the fucking z axis that I got pissed off
 
OH-IO ~Cult~
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Originally posted by seths99
calc 2 I could handle.
it was when I took calc 3 and they threw in the fucking z axis that I got pissed off


There's a goddamn Z AXIS?!?!?!



I'm just gonna be an art major...
 
Greenday4537
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Originally posted by OH-IO ~Cult~
There's a goddamn Z AXIS?!?!?!



I'm just gonna be an art major...


Communications
 
rams78110
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Why is this still here?
 
underdog13
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Originally posted by rams78110
Why is this still here?


why not
 
rams78110
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Because the last comment before mine was 8 months ago
 
foshizzel17
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Originally posted by rams78110
Because the last comment before mine was 8 months ago


everybody who was going to school is about to graduate. not many new users lately
 
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