Discover the Secrets of Specific Charge: Understanding the Example Sum

AI Thread Summary
The discussion revolves around understanding the calculation of specific charge using carbon-12 as an example. The user initially struggles with the exponent manipulation in the example sum, specifically how it transitions from -19 and 27 to a positive exponent. After posting their question, they realize the mistake in their own calculations, leading to the correct interpretation of the exponent rules. The conversation highlights the importance of understanding scientific notation in calculations. Ultimately, the user gains clarity on the topic after engaging with the forum.
bacardiancoke
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Hi all,

I'm reading through a section of my course about specific charge and I cannot figure out how exactly the example sum has got the answer it displays.

It uses carbon 12 as the example so displays the sum as:

= 9.61305876 x 10-19
------------------------------------------
20.08529244 x 10-27


= 0.4786118 x 10-19+27

= 0.4786118 x 108

= 4.4786118 x 107 Coulombs / kg

How exactly does it become (-19+27) when my working out of the very same sum has it at -46?

Thanks
 
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\frac{1}{10^n} = 10^{-n}

\frac{1}{10^{-n}} = 10^n
 
Thanks jtbell. :smile:

Was funny in a way, as soon as I hit "post" the penny dropped :redface:
 
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