Posted by rick on .
A laser emits 1.44*10^18 photons per second in a beam of light that has a diameter of 1.98 mm and a wavelength of 524.5 nm.
(a) Determine the average electric field strength
(b) Determine the average magnetic field strength for the electromagnetic wave that constitutes the beam.

physics 
bobpursley,
You know the energy (given wavelenght and the number of photons)
http://en.wikipedia.org/wiki/Poynting_vector
You know the Poynting vector (watts/m^2) in the beam, so figure E and B.
check my thinking. 
physics 
rick,
still don't understand where does wavelength and number of photons go too? do you divdide them to get energy or what?

physics 
bobpursley,
You get energy per photon from Planck's equation, then multiply by the nubmer to get joules/second (watts).