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### 1.9

Posted: **Mon Apr 16, 2018 1:15 pm**

by **Alysia Garcia 1B**

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?

### Re: 1.9

Posted: **Mon Apr 16, 2018 3:00 pm**

by **Chem_Mod**

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.

### Re: 1.9

Posted: **Thu Apr 19, 2018 5:32 pm**

by **Jocelyn Fermin1J**

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

### Re: 1.9

Posted: **Thu Apr 19, 2018 6:00 pm**

by **MadelynNguyen1F**

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

### Re: 1.9

Posted: **Thu Apr 19, 2018 8:09 pm**

by **Jared Pagal 1J**

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?

### Re: 1.9

Posted: **Fri Apr 20, 2018 9:35 am**

by **Beverly Shih 1K**

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.

### Re: 1.9

Posted: **Fri Apr 20, 2018 9:27 pm**

by **Gisselle Sainz 2F**

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