## Hw #1.67

$c=\lambda v$

Posts: 50
Joined: Fri Sep 29, 2017 7:05 am

### Hw #1.67

A team of scientist recently developed a series of nanowires that can act as miniature lasers.
a. one nanowire was found to emit light of frequency 6.27 x 10^14 Hz. What was the wavelength of the light emitted?
b. A second nanowire was found to emit light with a wavelength of 421nm. What was the frequency of the light from the second wire?

Grace Ramey 2K
Posts: 57
Joined: Thu Jul 27, 2017 3:01 am

### Re: Hw #1.67

For part a, you would use the equation c=λv, and rearrange the equation to give you λ (wavelength) = c (speed of light)/ v (frequency).

λ = (3.00 x 10^8 m/s)/(6.27 x 10^14 Hz) = 4.78 x 10^-7 m or 478 nm

For part b, use the same equation (c=λv), but rearrange it so that frequency is on one side of the equals sign, because it is the only unknown: v=c/λ.

(3.00 x 10^8 m/s)/(421 x 10^-9 m) = 7.12 x 10^14 Hz

Hope this helps!