5 x 10^7 kg of radioactive material emits energy in the form of photons of red light (700 nm). (Note: photons have no mass.)
What is the momentum of each photon?
We just started a new chapter, and in the process of learning it, I came across this question in the back of our book, which I am really having trouble understanding right now. Can anyone suggest how I can go about solving this (note, I would like to actually work out the problem myself; however, I need a sufficiant place to start.) Obviously, the Newtonian equations like
p =m/v will not apply here, so I'm somewhat stuck at the moment...
Any help is much appreciated, thank you.