1B.9 HW prob

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

Doris Cho 1D
Posts: 53
Joined: Thu Jul 11, 2019 12:16 am

1B.9 HW prob

I peeked at the solutions manual and was confused where the 64 J came from to find the number of protons. I found the 4.733 x 10^-19 J/photon^-1 but how do you know to divide 64 J by it?
also, just for clarification, when you find the amount of moles, is Avogadro's number used because photons are acting as "formula units"?

Andrew Jang 4D
Posts: 50
Joined: Sat Aug 17, 2019 12:18 am

Re: 1B.9 HW prob

The question says that the lamp is rated at 32 W or 32 J/s, and it asks for how many photons of light it generates in 2.0 seconds. 32 J/s * 2 s = 64 J. This is where that value comes from.