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Alysia Garcia 1B
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Postby Alysia Garcia 1B » Mon Apr 16, 2018 1:15 pm

For this problem, you are given the frequency 8.7x10^14 HZ. I understand that you have to divide that by the speed of light, 3.00x10^8 ms-1, to find the wavelength but how would you convert that to nm units?

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Re: 1.9

Postby Chem_Mod » Mon Apr 16, 2018 3:00 pm

First off, to find the wavelength, you actually divide the speed of light by frequency from the equation: . After finding wavelength, your answer should be in meters, m. To convert to nm, you should know that there are m in one nm.

Jocelyn Fermin1J
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Re: 1.9

Postby Jocelyn Fermin1J » Thu Apr 19, 2018 5:32 pm

I have stumbled on the frequency part; How would you convert MHz to Hz?

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Re: 1.9

Postby MadelynNguyen1F » Thu Apr 19, 2018 6:00 pm

1 MHz is equal to 10^6 Hz, so you would multiply by 10^6.

Jared Pagal 1J
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Re: 1.9

Postby Jared Pagal 1J » Thu Apr 19, 2018 8:09 pm

The second value in the table is given as Energy equals 3.3x10^-19 J. I divided by Planck's constant using the equation E=hv and the result was 4.980x10^14. Is it unusual to have a wavelength that long?

Beverly Shih 1K
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Re: 1.9

Postby Beverly Shih 1K » Fri Apr 20, 2018 9:35 am

I think what you calculated was actually frequency, not wavelength. In the equation E = hv, v stands for frequency so you would want to use E = hc/lambda and solve for lambda instead.
A wavelength of 4.980x10^14 Hz seems more than reasonable. For reference, red light has a frequency of about 4.3x10^14 Hz.

Gisselle Sainz 2F
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Re: 1.9

Postby Gisselle Sainz 2F » Fri Apr 20, 2018 9:27 pm

multiply (m) by 10^9 to get (nm)

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