Question

How many photons are in a laser pulse of 0.363J at 657 nm?

Answer 1

E=h*v
\[E=(h*c)/\]
E=((6.62*10^-34)*(3*10^8))/(657*10^-9)
E=3.025*10^-19 J, this is the energy of one photon
N=Np/Nph
N=(.363)/(3.025*10^-19)
N=119.9*10^16 photons