## 1.9

Alysia Garcia 1B
Posts: 40
Joined: Wed Feb 21, 2018 3:02 am

### 1.9

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?

Chem_Mod
Posts: 17489
Joined: Thu Aug 04, 2011 1:53 pm
Has upvoted: 393 times

### Re: 1.9

First off, to find the wavelength, you actually divide the speed of light by frequency from the equation: $c = \lambda * \nu$. After finding wavelength, your answer should be in meters, m. To convert to nm, you should know that there are $10^{-9}$m in one nm.

Jocelyn Fermin1J
Posts: 49
Joined: Tue Nov 14, 2017 3:01 am

### Re: 1.9

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

Posts: 59
Joined: Fri Apr 06, 2018 11:04 am

### Re: 1.9

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

Jared Pagal 1J
Posts: 24
Joined: Fri Apr 06, 2018 11:04 am

### Re: 1.9

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
Posts: 34
Joined: Wed Nov 15, 2017 3:01 am
Been upvoted: 1 time

### Re: 1.9

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
Posts: 76
Joined: Wed Feb 21, 2018 3:00 am

### Re: 1.9

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