Solving a Problem with 2.55 eV/4.14 x 10^-15 eVs

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The discussion revolves around a homework problem involving the calculation of frequency from energy values. The initial confusion arises from the division of 2.55 eV by 4.14 x 10^-15 eVs, leading to an expected frequency of 6.16 x 10^-16 Hz instead of the book's answer of 6.16 x 10^14 Hz. Participants clarify that the negative exponent in the denominator becomes positive when moved to the numerator, resulting in the correct frequency calculation. The key takeaway is understanding how to manipulate exponents during division. This clarification resolves the initial misunderstanding about the frequency value.
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Homework Statement



My book has a problem with a solution in which:

2.55 eV/4.14 x 10^-15 eVs = 6.16 x 10^ 14 Hz.

My question is:

I am trying to figure out why the answer is 10^14 when before they had 10^-15??
 
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domyy said:

Homework Statement



My book has a problem with a solution in which:

2.55 eV/4.14 x 10 to the power of -15 eVs = 6.16 x 10 the power of 14 Hz.

My question is:

I am trying to figure out why the answer is 10 to the power of 14 when before they had 10 to the power of -15??

What's 2.55/4.14? Express it in scientific notation.
 
2.55/4.14 = 0.616 approximately.
Then I say 6.16 x 10^-1
 
10^-1 x 10^-15 = 10^-16 not 10^14 as my book says.
 
domyy said:
2.55/4.14 = 0.616 approximately.
Then I say 6.16 x 10^-1
Correct.
domyy said:
10^-1 x 10^-15 = 10^-16 not 10^14 as my book says.
But the 10-15 is in the denominator. What happens to it when you 'promote' it to the numerator?
 
:smile::biggrin:ooooooooooooohhh I got it.
Thank you!:blushing:
 
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