## 1.59 6th edition

$\lambda=\frac{h}{p}$

Vanessa Reyes_1K
Posts: 60
Joined: Fri Sep 28, 2018 12:28 am

### 1.59 6th edition

Problem 1.59 reads: "Each second a certain lamp produces 9.8 x 10^20 photons with a wavelength of 434 nm. How much energy (in joules) is produced as radiation at this wavelength?". Where the does the number of photons fit into an equation?

Schuyler_Howell_4D
Posts: 66
Joined: Fri Sep 28, 2018 12:28 am
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### Re: 1.59 6th edition

Once you use the equation: E=hc(lambda)^-1
you will get energy in joules per photon. You then multiply that by 9.8 x 10^20 which is the number of photons.

(You should get 450 J. )