## Atomic Spectrum Module #28

$c=\lambda v$

melodyzaki2E
Posts: 61
Joined: Fri Sep 28, 2018 12:18 am

### Atomic Spectrum Module #28

In 1.0 s, a 60 W bulb emits 11 J of energy in the form of infrared radiation (heat) of wavelength 1850 nm. What is the energy per photon of light emitted? How many photons of infrared radiation does the lamp generate in 1.0 s?

Samantha Pacheco 2K
Posts: 60
Joined: Fri Sep 28, 2018 12:29 am

### Re: Atomic Spectrum Module #28

First you are going to convert the wave length from nm to meter. 1850nm= 1.85x10^-6 m. In order to find the # of photons first calculate the energy of each photon using E =hc/λ.
=(6.626 × 10−34 J · s)(3 × 108 m/s) /1.85 × 10−6 m
= 1.07449 × 10−19 J (per photon)
Now that you have the energy of one photon you are going to divide your total energy (11 J) by energy of each photon ( 1.07449 × 10−19 J)

# of photons= 11J/1.07449 × 10−19 J
= 1.02374 × 1020 photons