## Exercise 1A.7

$c=\lambda v$

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### Exercise 1A.7

Question: 1A.7 (a) The frequency of violet light is 7.1×10^14Hz. What is the wavelength (in nanometers) of violet light?
I know that I can use c=(lambda)(frequency) and rearrange it to find lambda which would be the wavelength, what I am questioning is how to go to nanometers since I am dividing meters per second by Hz. If anyone can go over it, I would be thankful.

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### Re: Exercise 1A.7

I haven't started that question yet, but from my understanding, 1 Hz is equal to 1 s^-1. Therefore, if you divide meters by seconds by Hz, the resulting unit is just meters, which you can then convert to nm. I hope this answered your question.

Melody Haratian 2J
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### Re: Exercise 1A.7

When you divide the speed of light which has units of meters per second (m/s), by hertz which has units of 1/seconds (s^-1 or 1/s), the seconds will cancel out and you’ll be left with meters. To convert the number you have in meters to nanometers, multiply by 10^9.

Crystal Pan 2G
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### Re: Exercise 1A.7

1 Hz= s^-1, so (m/s)/s^-1, so m/s x s, which cancels out s to get m for wavelength.

Bella Bursulaya 3G
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### Re: Exercise 1A.7

You'll get m for wavelength because lambda = m/s/1/s which is equal to m/s * s/1 so the s cancels out. To convert between m and nm, you need to know that there are 10^-9 m in 1 nm. Hope this helps!