MHz to Hz 1A.9


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Anna_Mohling_1D
Posts: 70
Joined: Wed Sep 30, 2020 9:56 pm

MHz to Hz 1A.9

Postby Anna_Mohling_1D » Wed Oct 21, 2020 2:11 pm

A college student recently had a busy day. Each of the student’s activities on that day (reading, getting a dental x-ray, making popcorn in a microwave oven, and acquiring a suntan) involved radiation from a different part of the electromagnetic spectrum. Complete the following table and match each type of radiation to the appropriate event:

Frequency Wavelength Energy of photon Event

8.7×10^14 Hz

3.3×10^−19 J

300 MHz

2.5 nm

I solved for all the 'blanks' in the box; however, for the wavelength corresponding to 300 MHz, I got 1m instead of 1nm. I multiplied 300MHz by 10^6 to get the frequency in Hz. I think solved for wavelength by doing c/frequency and got the wavelength to equal 1 m. I'm not sure where I messed up my units or how to fix it to get 1 nm.

Pranav Daggubati 3C
Posts: 109
Joined: Wed Sep 30, 2020 9:35 pm

Re: MHz to Hz 1A.9

Postby Pranav Daggubati 3C » Wed Oct 21, 2020 2:15 pm

The answer you got is correct, 300 MegaHertz frequency is equivalent to 1 meter in wavelength. You can see this because 300 MHz is the same as 3 x 10^8 Hz, which when multiplied by 1 equals the speed of light.

Chem_Mod
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Re: MHz to Hz 1A.9

Postby Chem_Mod » Wed Oct 21, 2020 2:16 pm

Hi Anna, your calculations are correct. The answer key in the back of the textbook has an error; however, you should be referring to the Student Solutions Manual to check your work; the answer is correct in the SSM.

Daniela_Martinez_3B
Posts: 51
Joined: Wed Sep 30, 2020 9:47 pm

Re: MHz to Hz 1A.9

Postby Daniela_Martinez_3B » Fri Oct 23, 2020 10:42 pm

The same thing happened to me! In case you couldn't find it, here's the link to the solution's manual with other errors from the textbook https://lavelle.chem.ucla.edu/wp-content/supporting-files/Chem14A/Solution_Manual_Errors_7Ed.pdf


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