Question

How many photons are produced in a laser pulse of 0.682 J at 655 nm? Answer needs to be in photons

Answer 1

E = n hc/ lamda

E = 0.682J

LAMDA= 655 nm = 655*10^-9 m

0.682= n* 6.625*10^-34*3*10^8/(655*10^-9)

n= 2.24*10^18 moles of PHOTONS

1 MOLE OF PHOTONS MENAS ---------------------------6.023*10^23 PHOTONS

2.24*10^18 MOLES OF PHOTONS MEANS ------------------------------?

              = 2.24*10^18*6.023*10^23

              = 1.34*10^42 PHOTONS